Add --audio-output-buffer

On some systems, the SDL audio callback is not called frequently enough
(for example it requests 5ms of samples every 10ms), because the output
buffer is too small.

By default, we want to use a small value (5ms) to minimize latency, but
if it does not work well, users need a way to increase it.

Refs #3793 <https://github.com/Genymobile/scrcpy/issues/3793>

FAQ.md

@@ -7,7 +7,7 @@ Here are the common reported problems and their status.
 If you encounter any error, the first step is to upgrade to the latest version.
 
 
-## `adb` issues
+## `adb` and USB issues
 
 `scrcpy` execute `adb` commands to initialize the connection with the device. If
 `adb` fails, then scrcpy will not work.
@@ -133,6 +133,21 @@ Try with another USB cable or plug it into another USB port. See [#281] and
 [#283]: https://github.com/Genymobile/scrcpy/issues/283
 
 
+## HID/OTG issues on Windows
+
+On Windows, if `scrcpy --otg` (or `--hid-keyboard`/`--hid-mouse`) results in:
+
+>     ERROR: Could not find any USB device
+
+(or if only unrelated USB devices are detected), there might be drivers issues.
+
+Please read [#3654], in particular [this comment][#3654-comment1] and [the next
+one][#3654-comment2].
+
+[#3654]: https://github.com/Genymobile/scrcpy/issues/3654
+[#3654-comment1]: https://github.com/Genymobile/scrcpy/issues/3654#issuecomment-1369278232
+[#3654-comment2]: https://github.com/Genymobile/scrcpy/issues/3654#issuecomment-1369295011
+
 
 ## Control issues
 
@@ -153,8 +168,7 @@ The default text injection method is [limited to ASCII characters][text-input].
 A trick allows to also inject some [accented characters][accented-characters],
 but that's all. See [#37].
 
-Since scrcpy v1.20 on Linux, it is possible to simulate a [physical
-keyboard][hid] (HID).
+Since scrcpy v1.20, it is possible to simulate a [physical keyboard][hid] (HID).
 
 [text-input]: https://github.com/Genymobile/scrcpy/issues?q=is%3Aopen+is%3Aissue+label%3Aunicode
 [accented-characters]: https://blog.rom1v.com/2018/03/introducing-scrcpy/#handle-accented-characters
@@ -164,32 +178,6 @@ keyboard][hid] (HID).
 
 ## Client issues
 
-### The quality is low
-
-If the definition of your client window is smaller than that of your device
-screen, then you might get poor quality, especially visible on text (see [#40]).
-
-[#40]: https://github.com/Genymobile/scrcpy/issues/40
-
-This problem should be fixed in scrcpy v1.22: **update to the latest version**.
-
-On older versions, you must configure the [scaling behavior]:
-
-> `scrcpy.exe` > Properties > Compatibility > Change high DPI settings >
-> Override high DPI scaling behavior > Scaling performed by: _Application_.
-
-[scaling behavior]: https://github.com/Genymobile/scrcpy/issues/40#issuecomment-424466723
-
-Also, to improve downscaling quality, trilinear filtering is enabled
-automatically if the renderer is OpenGL and if it supports mipmapping.
-
-On Windows, you might want to force OpenGL to enable mipmapping:
-
-```
-scrcpy --render-driver=opengl
-```
-
-
 ### Issue with Wayland
 
 By default, SDL uses x11 on Linux. The [video driver] can be changed via the
@@ -224,102 +212,15 @@ As a workaround, [disable "Block compositing"][kwin].
 
 ### Exception
 
-There may be many reasons. One common cause is that the hardware encoder of your
-device is not able to encode at the given definition:
-
-> ```
-> ERROR: Exception on thread Thread[main,5,main]
-> android.media.MediaCodec$CodecException: Error 0xfffffc0e
-> ...
-> Exit due to uncaughtException in main thread:
-> ERROR: Could not open video stream
-> INFO: Initial texture: 1080x2336
-> ```
-
-or
-
-> ```
-> ERROR: Exception on thread Thread[main,5,main]
-> java.lang.IllegalStateException
->         at android.media.MediaCodec.native_dequeueOutputBuffer(Native Method)
-> ```
-
-Just try with a lower definition:
+If you get any exception related to `MediaCodec`:
 
 ```
-scrcpy -m 1920
-scrcpy -m 1024
-scrcpy -m 800
+ERROR: Exception on thread Thread[main,5,main]
+java.lang.IllegalStateException
+        at android.media.MediaCodec.native_dequeueOutputBuffer(Native Method)
 ```
 
-Since scrcpy v1.22, scrcpy automatically tries again with a lower definition
-before failing. This behavior can be disabled with `--no-downsize-on-error`.
-
-You could also try another [encoder](README.md#encoder).
-
-
-If you encounter this exception on Android 12, then just upgrade to scrcpy >=
-1.18 (see [#2129]):
-
-```
-> ERROR: Exception on thread Thread[main,5,main]
-java.lang.AssertionError: java.lang.reflect.InvocationTargetException
-    at com.genymobile.scrcpy.wrappers.SurfaceControl.setDisplaySurface(SurfaceControl.java:75)
-    ...
-Caused by: java.lang.reflect.InvocationTargetException
-    at java.lang.reflect.Method.invoke(Native Method)
-    at com.genymobile.scrcpy.wrappers.SurfaceControl.setDisplaySurface(SurfaceControl.java:73)
-    ... 7 more
-Caused by: java.lang.IllegalArgumentException: displayToken must not be null
-    at android.view.SurfaceControl$Transaction.setDisplaySurface(SurfaceControl.java:3067)
-    at android.view.SurfaceControl.setDisplaySurface(SurfaceControl.java:2147)
-    ... 9 more
-```
-
-[#2129]: https://github.com/Genymobile/scrcpy/issues/2129
-
-
-## Command line on Windows
-
-Since v1.22, a "shortcut" has been added to directly open a terminal in the
-scrcpy directory. Double-click on `open_a_terminal_here.bat`, then type your
-command. For example:
-
-```
-scrcpy --record file.mkv
-```
-
-You could also open a terminal and go to the scrcpy folder manually:
-
- 1. Press <kbd>Windows</kbd>+<kbd>r</kbd>, this opens a dialog box.
- 2. Type `cmd` and press <kbd>Enter</kbd>, this opens a terminal.
- 3. Go to your _scrcpy_ directory, by typing (adapt the path):
-
-    ```bat
-    cd C:\Users\user\Downloads\scrcpy-win64-xxx
-    ```
-
-    and press <kbd>Enter</kbd>
- 4. Type your command. For example:
-
-    ```bat
-    scrcpy --record file.mkv
-    ```
-
-If you plan to always use the same arguments, create a file `myscrcpy.bat`
-(enable [show file extensions] to avoid confusion) in the `scrcpy` directory,
-containing your command. For example:
-
-```bat
-scrcpy --prefer-text --turn-screen-off --stay-awake
-```
-
-Then just double-click on that file.
-
-You could also edit (a copy of) `scrcpy-console.bat` or `scrcpy-noconsole.vbs`
-to add some arguments.
-
-[show file extensions]: https://www.howtogeek.com/205086/beginner-how-to-make-windows-show-file-extensions/
+then try with another [encoder](doc/video.md#codec).
 
 
 ## Translations

LICENSE

@@ -188,7 +188,7 @@
       identification within third-party archives.
 
    Copyright (C) 2018 Genymobile
-   Copyright (C) 2018-2022 Romain Vimont
+   Copyright (C) 2018-2023 Romain Vimont
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

app/data/bash-completion/scrcpy

@@ -45,6 +45,7 @@ _scrcpy() {
         -r --record=
         --record-format=
         --render-driver=
+        --require-audio
         --rotation=
         -s --serial=
         --shortcut-mod=
@@ -77,7 +78,7 @@ _scrcpy() {
             return
             ;;
         --audio-codec)
-            COMPREPLY=($(compgen -W 'opus aac' -- "$cur"))
+            COMPREPLY=($(compgen -W 'opus aac raw' -- "$cur"))
             return
             ;;
         --lock-video-orientation)

app/data/scrcpy-console.desktop

@@ -5,7 +5,7 @@ Comment=Display and control your Android device
 # For some users, the PATH or ADB environment variables are set from the shell
 # startup file, like .bashrc or .zshrc… Run an interactive shell to get
 # environment correctly initialized.
-Exec=/bin/bash --norc --noprofile -i -c '"$SHELL" -i -c scrcpy || read -p "Press any key to quit..."'
+Exec=/bin/bash --norc --noprofile -i -c "\"\\$SHELL\" -i -c scrcpy || read -p 'Press any key to quit...'"
 Icon=scrcpy
 Terminal=true
 Type=Application

app/data/scrcpy.desktop

@@ -5,7 +5,7 @@ Comment=Display and control your Android device
 # For some users, the PATH or ADB environment variables are set from the shell
 # startup file, like .bashrc or .zshrc… Run an interactive shell to get
 # environment correctly initialized.
-Exec=/bin/sh -c '"$SHELL" -i -c scrcpy'
+Exec=/bin/sh -c "\"\\$SHELL\" -i -c scrcpy"
 Icon=scrcpy
 Terminal=false
 Type=Application

app/data/zsh-completion/_scrcpy

@@ -10,7 +10,7 @@ local arguments
 arguments=(
     '--always-on-top[Make scrcpy window always on top \(above other windows\)]'
     '--audio-bit-rate=[Encode the audio at the given bit-rate]'
-    '--audio-codec=[Select the audio codec]:codec:(opus aac)'
+    '--audio-codec=[Select the audio codec]:codec:(opus aac raw)'
     '--audio-codec-options=[Set a list of comma-separated key\:type=value options for the device audio encoder]'
     '--audio-encoder=[Use a specific MediaCodec audio encoder]'
     {-b,--video-bit-rate=}'[Encode the video at the given bit-rate]'
@@ -51,6 +51,7 @@ arguments=(
     {-r,--record=}'[Record screen to file]:record file:_files'
     '--record-format=[Force recording format]:format:(mp4 mkv)'
     '--render-driver=[Request SDL to use the given render driver]:driver name:(direct3d opengl opengles2 opengles metal software)'
+    '--require-audio=[Make scrcpy fail if audio is enabled but does not work]'
     '--rotation=[Set the initial display rotation]:rotation values:(0 1 2 3)'
     {-s,--serial=}'[The device serial number \(mandatory for multiple devices only\)]:serial:($("${ADB-adb}" devices | awk '\''$2 == "device" {print $1}'\''))'
     '--shortcut-mod=[\[key1,key2+key3,...\] Specify the modifiers to use for scrcpy shortcuts]:shortcut mod:(lctrl rctrl lalt ralt lsuper rsuper)'

app/meson.build

@@ -11,6 +11,7 @@ src = [
     'src/control_msg.c',
     'src/controller.c',
     'src/decoder.c',
+    'src/delay_buffer.c',
     'src/demuxer.c',
     'src/device_msg.c',
     'src/icon.c',
@@ -29,7 +30,8 @@ src = [
     'src/screen.c',
     'src/server.c',
     'src/version.c',
-    'src/video_buffer.c',
+    'src/trait/frame_source.c',
+    'src/trait/packet_source.c',
     'src/util/acksync.c',
     'src/util/average.c',
     'src/util/bytebuf.c',
@@ -37,6 +39,7 @@ src = [
     'src/util/intmap.c',
     'src/util/intr.c',
     'src/util/log.c',
+    'src/util/memory.c',
     'src/util/net.c',
     'src/util/net_intr.c',
     'src/util/process.c',
@@ -173,6 +176,7 @@ check_functions = [
     'vasprintf',
     'nrand48',
     'jrand48',
+    'reallocarray',
 ]
 
 foreach f : check_functions
@@ -263,9 +267,6 @@ if get_option('buildtype') == 'debug'
             'tests/test_bytebuf.c',
             'src/util/bytebuf.c',
         ]],
-        ['test_cbuf', [
-            'tests/test_cbuf.c',
-        ]],
         ['test_cli', [
             'tests/test_cli.c',
             'src/cli.c',
@@ -290,9 +291,6 @@ if get_option('buildtype') == 'debug'
             'tests/test_device_msg_deserialize.c',
             'src/device_msg.c',
         ]],
-        ['test_queue', [
-            'tests/test_queue.c',
-        ]],
         ['test_strbuf', [
             'tests/test_strbuf.c',
             'src/util/strbuf.c',
@@ -302,6 +300,10 @@ if get_option('buildtype') == 'debug'
             'src/util/str.c',
             'src/util/strbuf.c',
         ]],
+        ['test_vecdeque', [
+            'tests/test_vecdeque.c',
+            'src/util/memory.c',
+        ]],
         ['test_vector', [
             'tests/test_vector.c',
         ]],

app/prebuilt-deps/prepare-adb.sh

@@ -6,10 +6,10 @@ cd "$DIR"
 mkdir -p "$PREBUILT_DATA_DIR"
 cd "$PREBUILT_DATA_DIR"
 
-DEP_DIR=platform-tools-33.0.3
+DEP_DIR=platform-tools-34.0.1
 
-FILENAME=platform-tools_r33.0.3-windows.zip
-SHA256SUM=1e59afd40a74c5c0eab0a9fad3f0faf8a674267106e0b19921be9f67081808c2
+FILENAME=platform-tools_r34.0.1-windows.zip
+SHA256SUM=5dd9c2be744c224fa3a7cbe30ba02d2cb378c763bd0f797a7e47e9f3156a5daa
 
 if [[ -d "$DEP_DIR" ]]
 then

app/prebuilt-deps/prepare-ffmpeg.sh

@@ -6,11 +6,11 @@ cd "$DIR"
 mkdir -p "$PREBUILT_DATA_DIR"
 cd "$PREBUILT_DATA_DIR"
 
-VERSION=6.0-scrcpy
+VERSION=6.0-scrcpy-2
 DEP_DIR="ffmpeg-$VERSION"
 
 FILENAME="$DEP_DIR".7z
-SHA256SUM=f3956295b4325a84aada05447ba3f314fbed96697811666d495de4de40d59f98
+SHA256SUM=98ef97f8607c97a5c4f9c5a0a991b78f105d002a3619145011d16ffb92501b14
 
 if [[ -d "$DEP_DIR" ]]
 then

app/prebuilt-deps/prepare-sdl.sh

@@ -6,10 +6,10 @@ cd "$DIR"
 mkdir -p "$PREBUILT_DATA_DIR"
 cd "$PREBUILT_DATA_DIR"
 
-DEP_DIR=SDL2-2.26.1
+DEP_DIR=SDL2-2.26.4
 
-FILENAME=SDL2-devel-2.26.1-mingw.tar.gz
-SHA256SUM=aa43e1531a89551f9f9e14b27953a81d4ac946a9e574b5813cd0f2b36e83cc1c
+FILENAME=SDL2-devel-2.26.4-mingw.tar.gz
+SHA256SUM=fe899c8642caac2f180b1ee6f786857ddcaa0adc1fa82474312b09dd47d74712
 
 if [[ -d "$DEP_DIR" ]]
 then

app/scrcpy-windows.rc

@@ -13,7 +13,7 @@ BEGIN
       VALUE "LegalCopyright", "Romain Vimont, Genymobile"
       VALUE "OriginalFilename", "scrcpy.exe"
       VALUE "ProductName", "scrcpy"
-      VALUE "ProductVersion", "1.25"
+      VALUE "ProductVersion", "2.0"
     END
   END
   BLOCK "VarFileInfo"

app/scrcpy.1

@@ -23,14 +23,40 @@ Make scrcpy window always on top (above other windows).
 .BI "\-\-audio\-bit\-rate " value
 Encode the audio at the given bit\-rate, expressed in bits/s. Unit suffixes are supported: '\fBK\fR' (x1000) and '\fBM\fR' (x1000000).
 
-Default is 196K (196000).
+Default is 128K (128000).
+
+.TP
+.BI "\-\-audio\-buffer ms
+Configure the audio buffering delay (in milliseconds).
+
+Lower values decrease the latency, but increase the likelyhood of buffer underrun (causing audio glitches).
+
+Default is 50.
+
+.TP
+.BI "\-\-audio\-output\-buffer ms
+Configure the size of the SDL audio output buffer (in milliseconds).
+
+If you get "robotic" audio playback, you should test with a higher value (10). Do not change this setting otherwise.
+
+Default is 5.
 
 .TP
 .BI "\-\-audio\-codec " name
-Select an audio codec (opus or aac).
+Select an audio codec (opus, aac or raw).
 
 Default is opus.
 
+.TP
+.BI "\-\-audio\-codec\-options " key\fR[:\fItype\fR]=\fIvalue\fR[,...]
+Set a list of comma-separated key:type=value options for the device audio encoder.
+
+The possible values for 'type' are 'int' (default), 'long', 'float' and 'string'.
+
+The list of possible codec options is available in the Android documentation
+.UR https://d.android.com/reference/android/media/MediaFormat
+.UE .
+
 .TP
 .BI "\-\-audio\-encoder " name
 Use a specific MediaCodec audio encoder (depending on the codec provided by \fB\-\-audio\-codec\fR).
@@ -262,6 +288,10 @@ Supported names are currently "direct3d", "opengl", "opengles2", "opengles", "me
 .UR https://wiki.libsdl.org/SDL_HINT_RENDER_DRIVER
 .UE
 
+.TP
+.B \-\-require\-audio
+By default, scrcpy mirrors only the video if audio capture fails on the device. This option makes scrcpy fail if audio is enabled but does not work.
+
 .TP
 .BI "\-\-rotation " value
 Set the initial display rotation. Possibles values are 0, 1, 2 and 3. Each increment adds a 90 degrees rotation counterclockwise.
@@ -549,7 +579,7 @@ Copyright \(co 2018 Genymobile
 Genymobile
 .UE
 
-Copyright \(co 2018\-2022
+Copyright \(co 2018\-2023
 .MT rom@rom1v.com
 Romain Vimont
 .ME

app/src/audio_player.c

@@ -1,93 +1,127 @@
 #include "audio_player.h"
 
+#include <libavcodec/avcodec.h>
 #include <libavutil/opt.h>
 
 #include "util/log.h"
 
 #define SC_AUDIO_PLAYER_NDEBUG // comment to debug
 
+/**
+ * Real-time audio player with configurable latency
+ *
+ * As input, the player regularly receives AVFrames of decoded audio samples.
+ * As output, an SDL callback regularly requests audio samples to be played.
+ * In the middle, an audio buffer stores the samples produced but not consumed
+ * yet.
+ *
+ * The goal of the player is to feed the audio output with a latency as low as
+ * possible while avoiding buffer underrun (i.e. not being able to provide
+ * samples when requested).
+ *
+ * The player aims to feed the audio output with as little latency as possible
+ * while avoiding buffer underrun. To achieve this, it attempts to maintain the
+ * average buffering (the number of samples present in the buffer) around a
+ * target value. If this target buffering is too low, then buffer underrun will
+ * occur frequently. If it is too high, then latency will become unacceptable.
+ * This target value is configured using the scrcpy option --audio-buffer.
+ *
+ * The player cannot adjust the sample input rate (it receives samples produced
+ * in real-time) or the sample output rate (it must provide samples as
+ * requested by the audio output callback). Therefore, it may only apply
+ * compensation by resampling (converting _m_ input samples to _n_ output
+ * samples).
+ *
+ * The compensation itself is applied by libswresample (FFmpeg). It is
+ * configured using swr_set_compensation(). An important work for the player
+ * is to estimate the compensation value regularly and apply it.
+ *
+ * The estimated buffering level is the result of averaging the "natural"
+ * buffering (samples are produced and consumed by blocks, so it must be
+ * smoothed), and making instant adjustments resulting of its own actions
+ * (explicit compensation and silence insertion on underflow), which are not
+ * smoothed.
+ *
+ * Buffer underflow events can occur when packets arrive too late. In that case,
+ * the player inserts silence. Once the packets finally arrive (late), one
+ * strategy could be to drop the samples that were replaced by silence, in
+ * order to keep a minimal latency. However, dropping samples in case of buffer
+ * underflow is inadvisable, as it would temporarily increase the underflow
+ * even more and cause very noticeable audio glitches.
+ *
+ * Therefore, the player doesn't drop any sample on underflow. The compensation
+ * mechanism will absorb the delay introduced by the inserted silence.
+ */
+
 /** Downcast frame_sink to sc_audio_player */
 #define DOWNCAST(SINK) container_of(SINK, struct sc_audio_player, frame_sink)
 
 #define SC_AV_SAMPLE_FMT AV_SAMPLE_FMT_FLT
 #define SC_SDL_SAMPLE_FMT AUDIO_F32
 
-#define SC_AUDIO_OUTPUT_BUFFER_SAMPLES 480 // 10ms at 48000Hz
+#define TO_BYTES(SAMPLES) sc_audiobuf_to_bytes(&ap->buf, (SAMPLES))
+#define TO_SAMPLES(BYTES) sc_audiobuf_to_samples(&ap->buf, (BYTES))
 
-// The target number of buffered samples between the producer and the consumer.
-// This value is directly use for compensation.
-#define SC_TARGET_BUFFERED_SAMPLES (3 * SC_AUDIO_OUTPUT_BUFFER_SAMPLES)
-
-// If the consumer is too late, skip samples to keep at most this value
-#define SC_BUFFERED_SAMPLES_THRESHOLD 2400 // 50ms at 48000Hz
-
-// Use a ring-buffer of 1 second (at 48000Hz) between the producer and the
-// consumer. It too big, but it guarantees that the producer and the consumer
-// will be able to access it in parallel without locking.
-#define SC_BYTEBUF_SIZE_IN_SAMPLES 48000
-
-void
+static void SDLCALL
 sc_audio_player_sdl_callback(void *userdata, uint8_t *stream, int len_int) {
     struct sc_audio_player *ap = userdata;
 
     // This callback is called with the lock used by SDL_AudioDeviceLock(), so
-    // the bytebuf is protected
+    // the audiobuf is protected
 
     assert(len_int > 0);
     size_t len = len_int;
+    uint32_t count = TO_SAMPLES(len);
 
 #ifndef SC_AUDIO_PLAYER_NDEBUG
-    LOGD("[Audio] SDL callback requests %" SC_PRIsizet " samples",
-         len / (ap->nb_channels * ap->out_bytes_per_sample));
+    LOGD("[Audio] SDL callback requests %" PRIu32 " samples", count);
 #endif
 
-    size_t read = sc_bytebuf_read_remaining(&ap->buf);
-    size_t max_buffered_bytes = SC_BUFFERED_SAMPLES_THRESHOLD
-                              * ap->nb_channels * ap->out_bytes_per_sample;
-    if (read > max_buffered_bytes + len) {
-        size_t skip = read - (max_buffered_bytes + len);
-#ifndef SC_AUDIO_PLAYER_NDEBUG
-        LOGD("[Audio] Buffered samples threshold exceeded: %" SC_PRIsizet
-             " bytes, skipping %" SC_PRIsizet " bytes", read, skip);
-#endif
-        // After this callback, exactly max_buffered_bytes will remain
-        sc_bytebuf_skip(&ap->buf, skip);
-        read = max_buffered_bytes + len;
-    }
-
-    // Number of buffered samples (may be negative on underflow)
-    float buffered_samples = ((float) read - len_int)
-                           / (ap->nb_channels * ap->out_bytes_per_sample);
-    sc_average_push(&ap->avg_buffered_samples, buffered_samples);
-
-    if (read) {
-        if (read > len) {
-            read = len;
+    uint32_t buffered_samples = sc_audiobuf_can_read(&ap->buf);
+    if (!ap->played) {
+        // Part of the buffering is handled by inserting initial silence. The
+        // remaining (margin) last samples will be handled by compensation.
+        uint32_t margin = 30 * ap->sample_rate / 1000; // 30ms
+        if (buffered_samples + margin < ap->target_buffering) {
+            LOGV("[Audio] Inserting initial buffering silence: %" PRIu32
+                 " samples", count);
+            // Delay playback starting to reach the target buffering. Fill the
+            // whole buffer with silence (len is small compared to the
+            // arbitrary margin value).
+            memset(stream, 0, len);
+            return;
         }
-        sc_bytebuf_read(&ap->buf, stream, read);
     }
 
-    if (read < len) {
-        // Insert silence
-#ifndef SC_AUDIO_PLAYER_NDEBUG
-        LOGD("[Audio] Buffer underflow, inserting silence: %" SC_PRIsizet
-             " bytes", len - read);
-#endif
-        memset(stream + read, 0, len - read);
+    uint32_t read = MIN(buffered_samples, count);
+    if (read) {
+        sc_audiobuf_read(&ap->buf, stream, read);
     }
-}
 
-static size_t
-sc_audio_player_get_buf_size(struct sc_audio_player *ap, size_t samples) {
-    assert(ap->nb_channels);
-    assert(ap->out_bytes_per_sample);
-    return samples * ap->nb_channels * ap->out_bytes_per_sample;
+    if (read < count) {
+        uint32_t silence = count - read;
+        // Insert silence. In theory, the inserted silent samples replace the
+        // missing real samples, which will arrive later, so they should be
+        // dropped to keep the latency minimal. However, this would cause very
+        // audible glitches, so let the clock compensation restore the target
+        // latency.
+        LOGD("[Audio] Buffer underflow, inserting silence: %" PRIu32 " samples",
+             silence);
+        memset(stream + read, 0, TO_BYTES(silence));
+
+        if (ap->received) {
+            // Inserting additional samples immediately increases buffering
+            ap->underflow += silence;
+        }
+    }
+
+    ap->played = true;
 }
 
 static uint8_t *
-sc_audio_player_get_swr_buf(struct sc_audio_player *ap, size_t min_samples) {
-    size_t min_buf_size = sc_audio_player_get_buf_size(ap, min_samples);
-    if (min_buf_size < ap->swr_buf_alloc_size) {
+sc_audio_player_get_swr_buf(struct sc_audio_player *ap, uint32_t min_samples) {
+    size_t min_buf_size = TO_BYTES(min_samples);
+    if (min_buf_size > ap->swr_buf_alloc_size) {
         size_t new_size = min_buf_size + 4096;
         uint8_t *buf = realloc(ap->swr_buf, new_size);
         if (!buf) {
@@ -102,6 +136,188 @@ sc_audio_player_get_swr_buf(struct sc_audio_player *ap, size_t min_samples) {
     return ap->swr_buf;
 }
 
+static bool
+sc_audio_player_frame_sink_push(struct sc_frame_sink *sink,
+                                const AVFrame *frame) {
+    struct sc_audio_player *ap = DOWNCAST(sink);
+
+    SwrContext *swr_ctx = ap->swr_ctx;
+
+    int64_t swr_delay = swr_get_delay(swr_ctx, ap->sample_rate);
+    // No need to av_rescale_rnd(), input and output sample rates are the same.
+    // Add more space (256) for clock compensation.
+    int dst_nb_samples = swr_delay + frame->nb_samples + 256;
+
+    uint8_t *swr_buf = sc_audio_player_get_swr_buf(ap, dst_nb_samples);
+    if (!swr_buf) {
+        return false;
+    }
+
+    int ret = swr_convert(swr_ctx, &swr_buf, dst_nb_samples,
+                          (const uint8_t **) frame->data, frame->nb_samples);
+    if (ret < 0) {
+        LOGE("Resampling failed: %d", ret);
+        return false;
+    }
+
+    // swr_convert() returns the number of samples which would have been
+    // written if the buffer was big enough.
+    uint32_t samples_written = MIN(ret, dst_nb_samples);
+#ifndef SC_AUDIO_PLAYER_NDEBUG
+    LOGD("[Audio] %" PRIu32 " samples written to buffer", samples_written);
+#endif
+
+    // Since this function is the only writer, the current available space is
+    // at least the previous available space. In practice, it should almost
+    // always be possible to write without lock.
+    bool lockless_write = samples_written <= ap->previous_can_write;
+    if (lockless_write) {
+        sc_audiobuf_prepare_write(&ap->buf, swr_buf, samples_written);
+    }
+
+    SDL_LockAudioDevice(ap->device);
+
+    uint32_t buffered_samples = sc_audiobuf_can_read(&ap->buf);
+
+    if (lockless_write) {
+        sc_audiobuf_commit_write(&ap->buf, samples_written);
+    } else {
+        uint32_t can_write = sc_audiobuf_can_write(&ap->buf);
+        if (samples_written > can_write) {
+            // Entering this branch is very unlikely, the audio buffer is
+            // allocated with a size sufficient to store 1 second more than the
+            // target buffering. If this happens, though, we have to skip old
+            // samples.
+            uint32_t cap = sc_audiobuf_capacity(&ap->buf);
+            if (samples_written > cap) {
+                // Very very unlikely: a single resampled frame should never
+                // exceed the audio buffer size (or something is very wrong).
+                // Ignore the first bytes in swr_buf
+                swr_buf += TO_BYTES(samples_written - cap);
+                // This change in samples_written will impact the
+                // instant_compensation below
+                samples_written = cap;
+            }
+
+            assert(samples_written >= can_write);
+            if (samples_written > can_write) {
+                uint32_t skip_samples = samples_written - can_write;
+                assert(buffered_samples >= skip_samples);
+                sc_audiobuf_skip(&ap->buf, skip_samples);
+                buffered_samples -= skip_samples;
+                if (ap->played) {
+                    // Dropping input samples instantly decreases buffering
+                    ap->avg_buffering.avg -= skip_samples;
+                }
+            }
+
+            // It should remain exactly the expected size to write the new
+            // samples.
+            assert(sc_audiobuf_can_write(&ap->buf) == samples_written);
+        }
+
+        sc_audiobuf_write(&ap->buf, swr_buf, samples_written);
+    }
+
+    buffered_samples += samples_written;
+    assert(buffered_samples == sc_audiobuf_can_read(&ap->buf));
+
+    // Read with lock held, to be used after unlocking
+    bool played = ap->played;
+    uint32_t underflow = ap->underflow;
+
+    if (played) {
+        uint32_t max_buffered_samples = ap->target_buffering
+                                      + 12 * ap->output_buffer
+                                      + ap->target_buffering / 10;
+        if (buffered_samples > max_buffered_samples) {
+            uint32_t skip_samples = buffered_samples - max_buffered_samples;
+            sc_audiobuf_skip(&ap->buf, skip_samples);
+            LOGD("[Audio] Buffering threshold exceeded, skipping %" PRIu32
+                 " samples", skip_samples);
+        }
+
+        // reset (the current value was copied to a local variable)
+        ap->underflow = 0;
+    } else {
+        // SDL playback not started yet, do not accumulate more than
+        // max_initial_buffering samples, this would cause unnecessary delay
+        // (and glitches to compensate) on start.
+        uint32_t max_initial_buffering = ap->target_buffering
+                                       + 2 * ap->output_buffer;
+        if (buffered_samples > max_initial_buffering) {
+            uint32_t skip_samples = buffered_samples - max_initial_buffering;
+            sc_audiobuf_skip(&ap->buf, skip_samples);
+#ifndef SC_AUDIO_PLAYER_NDEBUG
+            LOGD("[Audio] Playback not started, skipping %" PRIu32 " samples",
+                 skip_samples);
+#endif
+        }
+    }
+
+    ap->previous_can_write = sc_audiobuf_can_write(&ap->buf);
+    ap->received = true;
+
+    SDL_UnlockAudioDevice(ap->device);
+
+    if (played) {
+        // Number of samples added (or removed, if negative) for compensation
+        int32_t instant_compensation =
+            (int32_t) samples_written - frame->nb_samples;
+        int32_t inserted_silence = (int32_t) underflow;
+
+        // The compensation must apply instantly, it must not be smoothed
+        ap->avg_buffering.avg += instant_compensation + inserted_silence;
+
+
+        // However, the buffering level must be smoothed
+        sc_average_push(&ap->avg_buffering, buffered_samples);
+
+#ifndef SC_AUDIO_PLAYER_NDEBUG
+        LOGD("[Audio] buffered_samples=%" PRIu32 " avg_buffering=%f",
+             buffered_samples, sc_average_get(&ap->avg_buffering));
+#endif
+
+        ap->samples_since_resync += samples_written;
+        if (ap->samples_since_resync >= ap->sample_rate) {
+            // Recompute compensation every second
+            ap->samples_since_resync = 0;
+
+            float avg = sc_average_get(&ap->avg_buffering);
+            int diff = ap->target_buffering - avg;
+            if (abs(diff) < (int) ap->sample_rate / 1000) {
+                // Do not compensate for less than 1ms, the error is just noise
+                diff = 0;
+            } else if (diff < 0 && buffered_samples < ap->target_buffering) {
+                // Do not accelerate if the instant buffering level is below
+                // the average, this would increase underflow
+                diff = 0;
+            }
+            // Compensate the diff over 4 seconds (but will be recomputed after
+            // 1 second)
+            int distance = 4 * ap->sample_rate;
+            // Limit compensation rate to 2%
+            int abs_max_diff = distance / 50;
+            diff = CLAMP(diff, -abs_max_diff, abs_max_diff);
+            LOGV("[Audio] Buffering: target=%" PRIu32 " avg=%f cur=%" PRIu32
+                 " compensation=%d", ap->target_buffering, avg,
+                 buffered_samples, diff);
+
+            if (diff != ap->compensation) {
+                int ret = swr_set_compensation(swr_ctx, diff, distance);
+                if (ret < 0) {
+                    LOGW("Resampling compensation failed: %d", ret);
+                    // not fatal
+                } else {
+                    ap->compensation = diff;
+                }
+            }
+        }
+    }
+
+    return true;
+}
+
 static bool
 sc_audio_player_frame_sink_open(struct sc_frame_sink *sink,
                                 const AVCodecContext *ctx) {
@@ -115,11 +331,28 @@ sc_audio_player_frame_sink_open(struct sc_frame_sink *sink,
     unsigned nb_channels = tmp;
 #endif
 
+    assert(ctx->sample_rate > 0);
+    assert(!av_sample_fmt_is_planar(SC_AV_SAMPLE_FMT));
+    int out_bytes_per_sample = av_get_bytes_per_sample(SC_AV_SAMPLE_FMT);
+    assert(out_bytes_per_sample > 0);
+
+    ap->sample_rate = ctx->sample_rate;
+    ap->nb_channels = nb_channels;
+    ap->out_bytes_per_sample = out_bytes_per_sample;
+
+    ap->target_buffering = ap->target_buffering_delay * ap->sample_rate
+                                                      / SC_TICK_FREQ;
+
+    uint64_t aout_samples = ap->output_buffer_duration * ap->sample_rate
+                                                       / SC_TICK_FREQ;
+    assert(aout_samples <= 0xFFFF);
+    ap->output_buffer = (uint16_t) aout_samples;
+
     SDL_AudioSpec desired = {
         .freq = ctx->sample_rate,
         .format = SC_SDL_SAMPLE_FMT,
         .channels = nb_channels,
-        .samples = SC_AUDIO_OUTPUT_BUFFER_SAMPLES,
+        .samples = aout_samples,
         .callback = sc_audio_player_sdl_callback,
         .userdata = ap,
     };
@@ -138,12 +371,6 @@ sc_audio_player_frame_sink_open(struct sc_frame_sink *sink,
     }
     ap->swr_ctx = swr_ctx;
 
-    assert(ctx->sample_rate > 0);
-    assert(!av_sample_fmt_is_planar(SC_AV_SAMPLE_FMT));
-
-    int out_bytes_per_sample = av_get_bytes_per_sample(SC_AV_SAMPLE_FMT);
-    assert(out_bytes_per_sample > 0);
-
 #ifdef SCRCPY_LAVU_HAS_CHLAYOUT
     av_opt_set_chlayout(swr_ctx, "in_chlayout", &ctx->ch_layout, 0);
     av_opt_set_chlayout(swr_ctx, "out_chlayout", &ctx->ch_layout, 0);
@@ -166,37 +393,52 @@ sc_audio_player_frame_sink_open(struct sc_frame_sink *sink,
         goto error_free_swr_ctx;
     }
 
-    ap->sample_rate = ctx->sample_rate;
-    ap->nb_channels = nb_channels;
-    ap->out_bytes_per_sample = out_bytes_per_sample;
+    // Use a ring-buffer of the target buffering size plus 1 second between the
+    // producer and the consumer. It's too big on purpose, to guarantee that
+    // the producer and the consumer will be able to access it in parallel
+    // without locking.
+    size_t audiobuf_samples = ap->target_buffering + ap->sample_rate;
 
-    size_t bytebuf_size =
-        sc_audio_player_get_buf_size(ap, SC_BYTEBUF_SIZE_IN_SAMPLES);
-
-    bool ok = sc_bytebuf_init(&ap->buf, bytebuf_size);
+    size_t sample_size = ap->nb_channels * ap->out_bytes_per_sample;
+    bool ok = sc_audiobuf_init(&ap->buf, sample_size, audiobuf_samples);
     if (!ok) {
         goto error_free_swr_ctx;
     }
 
-    ap->safe_empty_buffer = sc_bytebuf_write_remaining(&ap->buf);
-
-    size_t initial_swr_buf_size = sc_audio_player_get_buf_size(ap, 4096);
+    size_t initial_swr_buf_size = TO_BYTES(4096);
     ap->swr_buf = malloc(initial_swr_buf_size);
     if (!ap->swr_buf) {
         LOG_OOM();
-        goto error_destroy_bytebuf;
+        goto error_destroy_audiobuf;
     }
     ap->swr_buf_alloc_size = initial_swr_buf_size;
 
-    sc_average_init(&ap->avg_buffered_samples, 32);
+    ap->previous_can_write = sc_audiobuf_can_write(&ap->buf);
+
+    // Samples are produced and consumed by blocks, so the buffering must be
+    // smoothed to get a relatively stable value.
+    sc_average_init(&ap->avg_buffering, 32);
     ap->samples_since_resync = 0;
 
+    ap->received = false;
+    ap->played = false;
+    ap->underflow = 0;
+    ap->compensation = 0;
+
+    // The thread calling open() is the thread calling push(), which fills the
+    // audio buffer consumed by the SDL audio thread.
+    ok = sc_thread_set_priority(SC_THREAD_PRIORITY_TIME_CRITICAL);
+    if (!ok) {
+        ok = sc_thread_set_priority(SC_THREAD_PRIORITY_HIGH);
+        (void) ok; // We don't care if it worked, at least we tried
+    }
+
     SDL_PauseAudioDevice(ap->device, 0);
 
     return true;
 
-error_destroy_bytebuf:
-    sc_bytebuf_destroy(&ap->buf);
+error_destroy_audiobuf:
+    sc_audiobuf_destroy(&ap->buf);
 error_free_swr_ctx:
     swr_free(&ap->swr_ctx);
 error_close_audio_device:
@@ -214,86 +456,16 @@ sc_audio_player_frame_sink_close(struct sc_frame_sink *sink) {
     SDL_CloseAudioDevice(ap->device);
 
     free(ap->swr_buf);
-    sc_bytebuf_destroy(&ap->buf);
+    sc_audiobuf_destroy(&ap->buf);
     swr_free(&ap->swr_ctx);
 }
 
-static bool
-sc_audio_player_frame_sink_push(struct sc_frame_sink *sink, const AVFrame *frame) {
-    struct sc_audio_player *ap = DOWNCAST(sink);
-
-    SwrContext *swr_ctx = ap->swr_ctx;
-
-    int64_t delay = swr_get_delay(swr_ctx, ap->sample_rate);
-    // No need to av_rescale_rnd(), input and output sample rates are the same
-    int dst_nb_samples = delay + frame->nb_samples;
-
-    uint8_t *swr_buf = sc_audio_player_get_swr_buf(ap, frame->nb_samples);
-    if (!swr_buf) {
-        return false;
-    }
-
-    int ret = swr_convert(swr_ctx, &swr_buf, dst_nb_samples,
-                          (const uint8_t **) frame->data, frame->nb_samples);
-    if (ret < 0) {
-        LOGE("Resampling failed: %d", ret);
-        return false;
-    }
-
-    size_t samples_written = ret;
-    size_t swr_buf_size = sc_audio_player_get_buf_size(ap, samples_written);
-#ifndef SC_AUDIO_PLAYER_NDEBUG
-    LOGI("[Audio] %" SC_PRIsizet " samples written to buffer", samples_written);
-#endif
-
-    // It should almost always be possible to write without lock
-    bool can_write_without_lock = swr_buf_size <= ap->safe_empty_buffer;
-    if (can_write_without_lock) {
-        sc_bytebuf_prepare_write(&ap->buf, swr_buf, swr_buf_size);
-    }
-
-    SDL_LockAudioDevice(ap->device);
-    if (can_write_without_lock) {
-        sc_bytebuf_commit_write(&ap->buf, swr_buf_size);
-    } else {
-        sc_bytebuf_write(&ap->buf, swr_buf, swr_buf_size);
-    }
-
-    // The next time, it will remain at least the current empty space
-    ap->safe_empty_buffer = sc_bytebuf_write_remaining(&ap->buf);
-
-    // Read the value written by the SDL thread under lock
-    float avg;
-    bool has_avg = sc_average_get(&ap->avg_buffered_samples, &avg);
-
-    SDL_UnlockAudioDevice(ap->device);
-
-    if (has_avg) {
-        ap->samples_since_resync += samples_written;
-        if (ap->samples_since_resync >= ap->sample_rate) {
-            // Resync every second
-            ap->samples_since_resync = 0;
-
-            int diff = SC_TARGET_BUFFERED_SAMPLES - avg;
-#ifndef SC_AUDIO_PLAYER_NDEBUG
-            LOGI("[Audio] Average buffered samples = %f, compensation %d",
-                 avg, diff);
-#endif
-            // Compensate the diff over 3 seconds (but will be recomputed after
-            // 1 second)
-            int ret = swr_set_compensation(swr_ctx, diff, 3 * ap->sample_rate);
-            if (ret < 0) {
-                LOGW("Resampling compensation failed: %d", ret);
-                // not fatal
-            }
-        }
-    }
-
-    return true;
-}
-
 void
-sc_audio_player_init(struct sc_audio_player *ap) {
+sc_audio_player_init(struct sc_audio_player *ap, sc_tick target_buffering,
+                     sc_tick output_buffer_duration) {
+    ap->target_buffering_delay = target_buffering;
+    ap->output_buffer_duration = output_buffer_duration;
+
     static const struct sc_frame_sink_ops ops = {
         .open = sc_audio_player_frame_sink_open,
         .close = sc_audio_player_frame_sink_close,

app/src/audio_player.h

@@ -5,9 +5,10 @@
 
 #include <stdbool.h>
 #include "trait/frame_sink.h"
+#include <util/audiobuf.h>
 #include <util/average.h>
-#include <util/bytebuf.h>
 #include <util/thread.h>
+#include <util/tick.h>
 
 #include <libavformat/avformat.h>
 #include <libswresample/swresample.h>
@@ -18,27 +19,61 @@ struct sc_audio_player {
 
     SDL_AudioDeviceID device;
 
-    // protected by SDL_AudioDeviceLock()
-    struct sc_bytebuf buf;
-    // Number of bytes which could be written without locking
-    size_t safe_empty_buffer;
+    // The target buffering between the producer and the consumer. This value
+    // is directly use for compensation.
+    // Since audio capture and/or encoding on the device typically produce
+    // blocks of 960 samples (20ms) or 1024 samples (~21.3ms), this target
+    // value should be higher.
+    sc_tick target_buffering_delay;
+    uint32_t target_buffering; // in samples
 
+    // SDL audio output buffer size.
+    sc_tick output_buffer_duration;
+    uint16_t output_buffer;
+
+    // Audio buffer to communicate between the receiver and the SDL audio
+    // callback (protected by SDL_AudioDeviceLock())
+    struct sc_audiobuf buf;
+
+    // The previous empty space in the buffer (only used by the receiver
+    // thread)
+    uint32_t previous_can_write;
+
+    // Resampler (only used from the receiver thread)
     struct SwrContext *swr_ctx;
 
     // The sample rate is the same for input and output
     unsigned sample_rate;
     // The number of channels is the same for input and output
     unsigned nb_channels;
-
+    // The number of bytes per sample for a single channel
     unsigned out_bytes_per_sample;
 
-    // Target buffer for resampling
+    // Target buffer for resampling (only used by the receiver thread)
     uint8_t *swr_buf;
     size_t swr_buf_alloc_size;
 
-    // Number of buffered samples (may be negative on underflow)
-    struct sc_average avg_buffered_samples;
-    unsigned samples_since_resync;
+    // Number of buffered samples (may be negative on underflow) (only used by
+    // the receiver thread)
+    struct sc_average avg_buffering;
+    // Count the number of samples to trigger a compensation update regularly
+    // (only used by the receiver thread)
+    uint32_t samples_since_resync;
+
+    // Number of silence samples inserted since the last received packet
+    // (protected by SDL_AudioDeviceLock())
+    uint32_t underflow;
+
+    // Current applied compensation value (only used by the receiver thread)
+    int compensation;
+
+    // Set to true the first time a sample is received (protected by
+    // SDL_AudioDeviceLock())
+    bool received;
+
+    // Set to true the first time the SDL callback is called (protected by
+    // SDL_AudioDeviceLock())
+    bool played;
 
     const struct sc_audio_player_callbacks *cbs;
     void *cbs_userdata;
@@ -49,6 +84,7 @@ struct sc_audio_player_callbacks {
 };
 
 void
-sc_audio_player_init(struct sc_audio_player *ap);
+sc_audio_player_init(struct sc_audio_player *ap, sc_tick target_buffering,
+                     sc_tick audio_output_buffer);
 
 #endif

app/src/cli.c

@@ -18,7 +18,7 @@
 #define STR(x) STR_IMPL_(x)
 
 enum {
-    OPT_RENDER_EXPIRED_FRAMES = 1000,
+    OPT_BIT_RATE = 1000,
     OPT_WINDOW_TITLE,
     OPT_PUSH_TARGET,
     OPT_ALWAYS_ON_TOP,
@@ -69,6 +69,9 @@ enum {
     OPT_AUDIO_ENCODER,
     OPT_LIST_ENCODERS,
     OPT_LIST_DISPLAYS,
+    OPT_REQUIRE_AUDIO,
+    OPT_AUDIO_BUFFER,
+    OPT_AUDIO_OUTPUT_BUFFER,
 };
 
 struct sc_option {
@@ -116,13 +119,32 @@ static const struct sc_option options[] = {
         .argdesc = "value",
         .text = "Encode the audio at the given bit-rate, expressed in bits/s. "
                 "Unit suffixes are supported: 'K' (x1000) and 'M' (x1000000).\n"
-                "Default is 196K (196000).",
+                "Default is 128K (128000).",
+    },
+    {
+        .longopt_id = OPT_AUDIO_BUFFER,
+        .longopt = "audio-buffer",
+        .argdesc = "ms",
+        .text = "Configure the audio buffering delay (in milliseconds).\n"
+                "Lower values decrease the latency, but increase the "
+                "likelyhood of buffer underrun (causing audio glitches).\n"
+                "Default is 50.",
+    },
+    {
+        .longopt_id = OPT_AUDIO_OUTPUT_BUFFER,
+        .longopt = "audio-output-buffer",
+        .argdesc = "ms",
+        .text = "Configure the size of the SDL audio output buffer (in "
+                "milliseconds).\n"
+                "If you get \"robotic\" audio playback, you should test with "
+                "a higher value (10). Do not change this setting otherwise.\n"
+                "Default is 5.",
     },
     {
         .longopt_id = OPT_AUDIO_CODEC,
         .longopt = "audio-codec",
         .argdesc = "name",
-        .text = "Select an audio codec (opus or aac).\n"
+        .text = "Select an audio codec (opus, aac or raw).\n"
                 "Default is opus.",
     },
     {
@@ -153,6 +175,12 @@ static const struct sc_option options[] = {
                 "Unit suffixes are supported: 'K' (x1000) and 'M' (x1000000).\n"
                 "Default is 8M (8000000).",
     },
+    {
+        // deprecated
+        .longopt_id = OPT_BIT_RATE,
+        .longopt = "bit-rate",
+        .argdesc = "value",
+    },
     {
         // Not really deprecated (--codec has never been released), but without
         // declaring an explicit --codec option, getopt_long() partial matching
@@ -454,9 +482,11 @@ static const struct sc_option options[] = {
                 "<https://wiki.libsdl.org/SDL_HINT_RENDER_DRIVER>",
     },
     {
-        // deprecated
-        .longopt_id = OPT_RENDER_EXPIRED_FRAMES,
-        .longopt = "render-expired-frames",
+        .longopt_id = OPT_REQUIRE_AUDIO,
+        .longopt = "require-audio",
+        .text = "By default, scrcpy mirrors only the video when audio capture "
+                "fails on the device. This option makes scrcpy fail if audio "
+                "is enabled but does not work."
     },
     {
         .longopt_id = OPT_ROTATION,
@@ -1185,6 +1215,19 @@ parse_buffering_time(const char *s, sc_tick *tick) {
     return true;
 }
 
+static bool
+parse_audio_output_buffer(const char *s, sc_tick *tick) {
+    long value;
+    bool ok = parse_integer_arg(s, &value, false, 0, 1000,
+                                "audio output buffer");
+    if (!ok) {
+        return false;
+    }
+
+    *tick = SC_TICK_FROM_MS(value);
+    return true;
+}
+
 static bool
 parse_lock_video_orientation(const char *s,
                              enum sc_lock_video_orientation *lock_mode) {
@@ -1497,7 +1540,11 @@ parse_audio_codec(const char *optarg, enum sc_codec *codec) {
         *codec = SC_CODEC_AAC;
         return true;
     }
-    LOGE("Unsupported audio codec: %s (expected opus)", optarg);
+    if (!strcmp(optarg, "raw")) {
+        *codec = SC_CODEC_RAW;
+        return true;
+    }
+    LOGE("Unsupported audio codec: %s (expected opus, aac or raw)", optarg);
     return false;
 }
 
@@ -1511,6 +1558,10 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
     int c;
     while ((c = getopt_long(argc, argv, optstring, longopts, NULL)) != -1) {
         switch (c) {
+            case OPT_BIT_RATE:
+                LOGE("--bit-rate has been removed, "
+                     "use --video-bit-rate or --audio-bit-rate.");
+                return false;
             case 'b':
                 if (!parse_bit_rate(optarg, &opts->video_bit_rate)) {
                     return false;
@@ -1538,9 +1589,6 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case 'f':
                 opts->fullscreen = true;
                 break;
-            case 'F':
-                LOGW("Deprecated option -F. Use --record-format instead.");
-                // fall through
             case OPT_RECORD_FORMAT:
                 if (!parse_record_format(optarg, &opts->record_format)) {
                     return false;
@@ -1628,10 +1676,6 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case 'w':
                 opts->stay_awake = true;
                 break;
-            case OPT_RENDER_EXPIRED_FRAMES:
-                LOGW("Option --render-expired-frames has been removed. This "
-                     "flag has been ignored.");
-                break;
             case OPT_WINDOW_TITLE:
                 opts->window_title = optarg;
                 break;
@@ -1690,9 +1734,9 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                 opts->forward_key_repeat = false;
                 break;
             case OPT_CODEC_OPTIONS:
-                LOGW("--codec-options is deprecated, use --video-codec-options "
-                     "instead.");
-                // fall through
+                LOGE("--codec-options has been removed, "
+                     "use --video-codec-options or --audio-codec-options.");
+                return false;
             case OPT_VIDEO_CODEC_OPTIONS:
                 opts->video_codec_options = optarg;
                 break;
@@ -1700,8 +1744,9 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                 opts->audio_codec_options = optarg;
                 break;
             case OPT_ENCODER:
-                LOGW("--encoder is deprecated, use --video-encoder instead.");
-                // fall through
+                LOGE("--encoder has been removed, "
+                     "use --video-encoder or --audio-encoder.");
+                return false;
             case OPT_VIDEO_ENCODER:
                 opts->video_encoder = optarg;
                 break;
@@ -1756,8 +1801,9 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                 opts->start_fps_counter = true;
                 break;
             case OPT_CODEC:
-                LOGW("--codec is deprecated, use --video-codec instead.");
-                // fall through
+                LOGE("--codec has been removed, "
+                     "use --video-codec or --audio-codec.");
+                return false;
             case OPT_VIDEO_CODEC:
                 if (!parse_video_codec(optarg, &opts->video_codec)) {
                     return false;
@@ -1801,6 +1847,20 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case OPT_LIST_DISPLAYS:
                 opts->list_displays = true;
                 break;
+            case OPT_REQUIRE_AUDIO:
+                opts->require_audio = true;
+                break;
+            case OPT_AUDIO_BUFFER:
+                if (!parse_buffering_time(optarg, &opts->audio_buffer)) {
+                    return false;
+                }
+                break;
+            case OPT_AUDIO_OUTPUT_BUFFER:
+                if (!parse_audio_output_buffer(optarg,
+                                               &opts->audio_output_buffer)) {
+                    return false;
+                }
+                break;
             default:
                 // getopt prints the error message on stderr
                 return false;
@@ -1861,6 +1921,11 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
     }
 #endif
 
+    if (opts->audio && !opts->display && !opts->record_filename) {
+        LOGI("No display and no recording: audio disabled");
+        opts->audio = false;
+    }
+
     if ((opts->tunnel_host || opts->tunnel_port) && !opts->force_adb_forward) {
         LOGI("Tunnel host/port is set, "
              "--force-adb-forward automatically enabled.");
@@ -1882,6 +1947,23 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
         }
     }
 
+    if (opts->record_filename && opts->audio_codec == SC_CODEC_RAW) {
+        LOGW("Recording does not support RAW audio codec");
+        return false;
+    }
+
+    if (opts->audio_codec == SC_CODEC_RAW) {
+        if (opts->audio_bit_rate) {
+            LOGW("--audio-bit-rate is ignored for raw audio codec");
+        }
+        if (opts->audio_codec_options) {
+            LOGW("--audio-codec-options is ignored for raw audio codec");
+        }
+        if (opts->audio_encoder) {
+            LOGW("--audio-encoder is ignored for raw audio codec");
+        }
+    }
+
     if (!opts->control) {
         if (opts->turn_screen_off) {
             LOGE("Could not request to turn screen off if control is disabled");

app/src/clock.c

@@ -18,7 +18,15 @@ sc_clock_init(struct sc_clock *clock) {
 static void
 sc_clock_estimate(struct sc_clock *clock,
                   double *out_slope, sc_tick *out_offset) {
-    assert(clock->count > 1); // two points are necessary
+    assert(clock->count);
+
+    if (clock->count == 1) {
+        // If there is only 1 point, we can't compute a slope. Assume it is 1.
+        struct sc_clock_point *single_point = &clock->right_sum;
+        *out_slope = 1;
+        *out_offset = single_point->system - single_point->stream;
+        return;
+    }
 
     struct sc_clock_point left_avg = {
         .system = clock->left_sum.system / (clock->count / 2),
@@ -93,19 +101,16 @@ sc_clock_update(struct sc_clock *clock, sc_tick system, sc_tick stream) {
 
     clock->head = (clock->head + 1) % SC_CLOCK_RANGE;
 
-    if (clock->count > 1) {
-        // Update estimation
-        sc_clock_estimate(clock, &clock->slope, &clock->offset);
+    // Update estimation
+    sc_clock_estimate(clock, &clock->slope, &clock->offset);
 
 #ifndef SC_CLOCK_NDEBUG
-        LOGD("Clock estimation: %f * pts + %" PRItick,
-             clock->slope, clock->offset);
+    LOGD("Clock estimation: %f * pts + %" PRItick, clock->slope, clock->offset);
 #endif
-    }
 }
 
 sc_tick
 sc_clock_to_system_time(struct sc_clock *clock, sc_tick stream) {
-    assert(clock->count > 1); // sc_clock_update() must have been called
+    assert(clock->count); // sc_clock_update() must have been called
     return (sc_tick) (stream * clock->slope) + clock->offset;
 }

app/src/common.h

@@ -5,8 +5,8 @@
 #include "compat.h"
 
 #define ARRAY_LEN(a) (sizeof(a) / sizeof(a[0]))
-#define MIN(X,Y) (X) < (Y) ? (X) : (Y)
-#define MAX(X,Y) (X) > (Y) ? (X) : (Y)
+#define MIN(X,Y) ((X) < (Y) ? (X) : (Y))
+#define MAX(X,Y) ((X) > (Y) ? (X) : (Y))
 #define CLAMP(V,X,Y) MIN( MAX((V),(X)), (Y) )
 
 #define container_of(ptr, type, member) \

app/src/compat.c

@@ -3,6 +3,9 @@
 #include "config.h"
 
 #include <assert.h>
+#ifndef HAVE_REALLOCARRAY
+# include <errno.h>
+#endif
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
@@ -93,5 +96,15 @@ long jrand48(unsigned short xsubi[3]) {
     return v.i;
 }
 #endif
-
+#endif
+
+#ifndef HAVE_REALLOCARRAY
+void *reallocarray(void *ptr, size_t nmemb, size_t size) {
+    size_t bytes;
+    if (__builtin_mul_overflow(nmemb, size, &bytes)) {
+      errno = ENOMEM;
+      return NULL;
+    }
+    return realloc(ptr, bytes);
+}
 #endif

app/src/compat.h

@@ -54,6 +54,10 @@
 # define SCRCPY_SDL_HAS_HINT_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR
 #endif
 
+#if SDL_VERSION_ATLEAST(2, 0, 16)
+# define SCRCPY_SDL_HAS_THREAD_PRIORITY_TIME_CRITICAL
+#endif
+
 #ifndef HAVE_STRDUP
 char *strdup(const char *s);
 #endif
@@ -74,4 +78,8 @@ long nrand48(unsigned short xsubi[3]);
 long jrand48(unsigned short xsubi[3]);
 #endif
 
+#ifndef HAVE_REALLOCARRAY
+void *reallocarray(void *ptr, size_t nmemb, size_t size);
+#endif
+
 #endif

app/src/controller.c

@@ -4,19 +4,28 @@
 
 #include "util/log.h"
 
+#define SC_CONTROL_MSG_QUEUE_MAX 64
+
 bool
 sc_controller_init(struct sc_controller *controller, sc_socket control_socket,
                    struct sc_acksync *acksync) {
-    cbuf_init(&controller->queue);
+    sc_vecdeque_init(&controller->queue);
 
-    bool ok = sc_receiver_init(&controller->receiver, control_socket, acksync);
+    bool ok = sc_vecdeque_reserve(&controller->queue, SC_CONTROL_MSG_QUEUE_MAX);
     if (!ok) {
         return false;
     }
 
+    ok = sc_receiver_init(&controller->receiver, control_socket, acksync);
+    if (!ok) {
+        sc_vecdeque_destroy(&controller->queue);
+        return false;
+    }
+
     ok = sc_mutex_init(&controller->mutex);
     if (!ok) {
         sc_receiver_destroy(&controller->receiver);
+        sc_vecdeque_destroy(&controller->queue);
         return false;
     }
 
@@ -24,6 +33,7 @@ sc_controller_init(struct sc_controller *controller, sc_socket control_socket,
     if (!ok) {
         sc_receiver_destroy(&controller->receiver);
         sc_mutex_destroy(&controller->mutex);
+        sc_vecdeque_destroy(&controller->queue);
         return false;
     }
 
@@ -38,10 +48,12 @@ sc_controller_destroy(struct sc_controller *controller) {
     sc_cond_destroy(&controller->msg_cond);
     sc_mutex_destroy(&controller->mutex);
 
-    struct sc_control_msg msg;
-    while (cbuf_take(&controller->queue, &msg)) {
-        sc_control_msg_destroy(&msg);
+    while (!sc_vecdeque_is_empty(&controller->queue)) {
+        struct sc_control_msg *msg = sc_vecdeque_popref(&controller->queue);
+        assert(msg);
+        sc_control_msg_destroy(msg);
     }
+    sc_vecdeque_destroy(&controller->queue);
 
     sc_receiver_destroy(&controller->receiver);
 }
@@ -54,13 +66,19 @@ sc_controller_push_msg(struct sc_controller *controller,
     }
 
     sc_mutex_lock(&controller->mutex);
-    bool was_empty = cbuf_is_empty(&controller->queue);
-    bool res = cbuf_push(&controller->queue, *msg);
-    if (was_empty) {
-        sc_cond_signal(&controller->msg_cond);
+    bool full = sc_vecdeque_is_full(&controller->queue);
+    if (!full) {
+        bool was_empty = sc_vecdeque_is_empty(&controller->queue);
+        sc_vecdeque_push_noresize(&controller->queue, *msg);
+        if (was_empty) {
+            sc_cond_signal(&controller->msg_cond);
+        }
     }
+    // Otherwise (if the queue is full), the msg is discarded
+
     sc_mutex_unlock(&controller->mutex);
-    return res;
+
+    return !full;
 }
 
 static bool
@@ -82,7 +100,8 @@ run_controller(void *data) {
 
     for (;;) {
         sc_mutex_lock(&controller->mutex);
-        while (!controller->stopped && cbuf_is_empty(&controller->queue)) {
+        while (!controller->stopped
+                && sc_vecdeque_is_empty(&controller->queue)) {
             sc_cond_wait(&controller->msg_cond, &controller->mutex);
         }
         if (controller->stopped) {
@@ -90,10 +109,9 @@ run_controller(void *data) {
             sc_mutex_unlock(&controller->mutex);
             break;
         }
-        struct sc_control_msg msg;
-        bool non_empty = cbuf_take(&controller->queue, &msg);
-        assert(non_empty);
-        (void) non_empty;
+
+        assert(!sc_vecdeque_is_empty(&controller->queue));
+        struct sc_control_msg msg = sc_vecdeque_pop(&controller->queue);
         sc_mutex_unlock(&controller->mutex);
 
         bool ok = process_msg(controller, &msg);

app/src/controller.h

@@ -8,11 +8,11 @@
 #include "control_msg.h"
 #include "receiver.h"
 #include "util/acksync.h"
-#include "util/cbuf.h"
 #include "util/net.h"
 #include "util/thread.h"
+#include "util/vecdeque.h"
 
-struct sc_control_msg_queue CBUF(struct sc_control_msg, 64);
+struct sc_control_msg_queue SC_VECDEQUE(struct sc_control_msg);
 
 struct sc_controller {
     sc_socket control_socket;

app/src/decoder.c

@@ -5,106 +5,34 @@
 #include <libavutil/channel_layout.h>
 
 #include "events.h"
-#include "video_buffer.h"
 #include "trait/frame_sink.h"
 #include "util/log.h"
 
 /** Downcast packet_sink to decoder */
 #define DOWNCAST(SINK) container_of(SINK, struct sc_decoder, packet_sink)
 
-static void
-sc_decoder_close_first_sinks(struct sc_decoder *decoder, unsigned count) {
-    while (count) {
-        struct sc_frame_sink *sink = decoder->sinks[--count];
-        sink->ops->close(sink);
-    }
-}
-
-static inline void
-sc_decoder_close_sinks(struct sc_decoder *decoder) {
-    sc_decoder_close_first_sinks(decoder, decoder->sink_count);
-}
-
 static bool
-sc_decoder_open_sinks(struct sc_decoder *decoder, const AVCodecContext *ctx) {
-    for (unsigned i = 0; i < decoder->sink_count; ++i) {
-        struct sc_frame_sink *sink = decoder->sinks[i];
-        if (!sink->ops->open(sink, ctx)) {
-            sc_decoder_close_first_sinks(decoder, i);
-            return false;
-        }
-    }
-
-    return true;
-}
-
-static bool
-sc_decoder_open(struct sc_decoder *decoder, const AVCodec *codec) {
-    decoder->codec_ctx = avcodec_alloc_context3(codec);
-    if (!decoder->codec_ctx) {
-        LOG_OOM();
-        return false;
-    }
-
-    decoder->codec_ctx->flags |= AV_CODEC_FLAG_LOW_DELAY;
-
-    if (codec->type == AVMEDIA_TYPE_VIDEO) {
-        // Hardcoded video properties
-        decoder->codec_ctx->pix_fmt = AV_PIX_FMT_YUV420P;
-    } else {
-        // Hardcoded audio properties
-#ifdef SCRCPY_LAVU_HAS_CHLAYOUT
-        decoder->codec_ctx->ch_layout =
-            (AVChannelLayout) AV_CHANNEL_LAYOUT_STEREO;
-#else
-        decoder->codec_ctx->channel_layout = AV_CH_LAYOUT_STEREO;
-        decoder->codec_ctx->channels = 2;
-#endif
-        decoder->codec_ctx->sample_rate = 48000;
-    }
-
-    if (avcodec_open2(decoder->codec_ctx, codec, NULL) < 0) {
-        LOGE("Decoder '%s': could not open codec", decoder->name);
-        avcodec_free_context(&decoder->codec_ctx);
-        return false;
-    }
-
+sc_decoder_open(struct sc_decoder *decoder, AVCodecContext *ctx) {
     decoder->frame = av_frame_alloc();
     if (!decoder->frame) {
         LOG_OOM();
-        avcodec_close(decoder->codec_ctx);
-        avcodec_free_context(&decoder->codec_ctx);
         return false;
     }
 
-    if (!sc_decoder_open_sinks(decoder, decoder->codec_ctx)) {
+    if (!sc_frame_source_sinks_open(&decoder->frame_source, ctx)) {
         av_frame_free(&decoder->frame);
-        avcodec_close(decoder->codec_ctx);
-        avcodec_free_context(&decoder->codec_ctx);
         return false;
     }
 
+    decoder->ctx = ctx;
+
     return true;
 }
 
 static void
 sc_decoder_close(struct sc_decoder *decoder) {
-    sc_decoder_close_sinks(decoder);
+    sc_frame_source_sinks_close(&decoder->frame_source);
     av_frame_free(&decoder->frame);
-    avcodec_close(decoder->codec_ctx);
-    avcodec_free_context(&decoder->codec_ctx);
-}
-
-static bool
-push_frame_to_sinks(struct sc_decoder *decoder, const AVFrame *frame) {
-    for (unsigned i = 0; i < decoder->sink_count; ++i) {
-        struct sc_frame_sink *sink = decoder->sinks[i];
-        if (!sink->ops->push(sink, frame)) {
-            return false;
-        }
-    }
-
-    return true;
 }
 
 static bool
@@ -115,33 +43,42 @@ sc_decoder_push(struct sc_decoder *decoder, const AVPacket *packet) {
         return true;
     }
 
-    int ret = avcodec_send_packet(decoder->codec_ctx, packet);
+    int ret = avcodec_send_packet(decoder->ctx, packet);
     if (ret < 0 && ret != AVERROR(EAGAIN)) {
         LOGE("Decoder '%s': could not send video packet: %d",
              decoder->name, ret);
         return false;
     }
-    ret = avcodec_receive_frame(decoder->codec_ctx, decoder->frame);
-    if (!ret) {
-        // a frame was received
-        bool ok = push_frame_to_sinks(decoder, decoder->frame);
-        // A frame lost should not make the whole pipeline fail. The error, if
-        // any, is already logged.
-        (void) ok;
 
+    for (;;) {
+        ret = avcodec_receive_frame(decoder->ctx, decoder->frame);
+        if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
+            break;
+        }
+
+        if (ret) {
+            LOGE("Decoder '%s', could not receive video frame: %d",
+                 decoder->name, ret);
+            return false;
+        }
+
+        // a frame was received
+        bool ok = sc_frame_source_sinks_push(&decoder->frame_source,
+                                             decoder->frame);
         av_frame_unref(decoder->frame);
-    } else if (ret != AVERROR(EAGAIN)) {
-        LOGE("Decoder '%s', could not receive video frame: %d",
-             decoder->name, ret);
-        return false;
+        if (!ok) {
+            // Error already logged
+            return false;
+        }
     }
+
     return true;
 }
 
 static bool
-sc_decoder_packet_sink_open(struct sc_packet_sink *sink, const AVCodec *codec) {
+sc_decoder_packet_sink_open(struct sc_packet_sink *sink, AVCodecContext *ctx) {
     struct sc_decoder *decoder = DOWNCAST(sink);
-    return sc_decoder_open(decoder, codec);
+    return sc_decoder_open(decoder, ctx);
 }
 
 static void
@@ -160,7 +97,7 @@ sc_decoder_packet_sink_push(struct sc_packet_sink *sink,
 void
 sc_decoder_init(struct sc_decoder *decoder, const char *name) {
     decoder->name = name; // statically allocated
-    decoder->sink_count = 0;
+    sc_frame_source_init(&decoder->frame_source);
 
     static const struct sc_packet_sink_ops ops = {
         .open = sc_decoder_packet_sink_open,
@@ -170,11 +107,3 @@ sc_decoder_init(struct sc_decoder *decoder, const char *name) {
 
     decoder->packet_sink.ops = &ops;
 }
-
-void
-sc_decoder_add_sink(struct sc_decoder *decoder, struct sc_frame_sink *sink) {
-    assert(decoder->sink_count < SC_DECODER_MAX_SINKS);
-    assert(sink);
-    assert(sink->ops);
-    decoder->sinks[decoder->sink_count++] = sink;
-}

app/src/decoder.h

@@ -3,23 +3,20 @@
 
 #include "common.h"
 
+#include "trait/frame_source.h"
 #include "trait/packet_sink.h"
 
 #include <stdbool.h>
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
 
-#define SC_DECODER_MAX_SINKS 2
-
 struct sc_decoder {
     struct sc_packet_sink packet_sink; // packet sink trait
+    struct sc_frame_source frame_source; // frame source trait
 
     const char *name; // must be statically allocated (e.g. a string literal)
 
-    struct sc_frame_sink *sinks[SC_DECODER_MAX_SINKS];
-    unsigned sink_count;
-
-    AVCodecContext *codec_ctx;
+    AVCodecContext *ctx;
     AVFrame *frame;
 };
 
@@ -27,7 +24,4 @@ struct sc_decoder {
 void
 sc_decoder_init(struct sc_decoder *decoder, const char *name);
 
-void
-sc_decoder_add_sink(struct sc_decoder *decoder, struct sc_frame_sink *sink);
-
 #endif

app/src/delay_buffer.c

@@ -0,0 +1,244 @@
+#include "delay_buffer.h"
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include <libavutil/avutil.h>
+#include <libavformat/avformat.h>
+
+#include "util/log.h"
+
+#define SC_BUFFERING_NDEBUG // comment to debug
+
+/** Downcast frame_sink to sc_delay_buffer */
+#define DOWNCAST(SINK) container_of(SINK, struct sc_delay_buffer, frame_sink)
+
+static bool
+sc_delayed_frame_init(struct sc_delayed_frame *dframe, const AVFrame *frame) {
+    dframe->frame = av_frame_alloc();
+    if (!dframe->frame) {
+        LOG_OOM();
+        return false;
+    }
+
+    if (av_frame_ref(dframe->frame, frame)) {
+        LOG_OOM();
+        av_frame_free(&dframe->frame);
+        return false;
+    }
+
+    return true;
+}
+
+static void
+sc_delayed_frame_destroy(struct sc_delayed_frame *dframe) {
+    av_frame_unref(dframe->frame);
+    av_frame_free(&dframe->frame);
+}
+
+static int
+run_buffering(void *data) {
+    struct sc_delay_buffer *db = data;
+
+    assert(db->delay > 0);
+
+    for (;;) {
+        sc_mutex_lock(&db->mutex);
+
+        while (!db->stopped && sc_vecdeque_is_empty(&db->queue)) {
+            sc_cond_wait(&db->queue_cond, &db->mutex);
+        }
+
+        if (db->stopped) {
+            sc_mutex_unlock(&db->mutex);
+            goto stopped;
+        }
+
+        struct sc_delayed_frame dframe = sc_vecdeque_pop(&db->queue);
+
+        sc_tick max_deadline = sc_tick_now() + db->delay;
+        // PTS (written by the server) are expressed in microseconds
+        sc_tick pts = SC_TICK_FROM_US(dframe.frame->pts);
+
+        bool timed_out = false;
+        while (!db->stopped && !timed_out) {
+            sc_tick deadline = sc_clock_to_system_time(&db->clock, pts)
+                             + db->delay;
+            if (deadline > max_deadline) {
+                deadline = max_deadline;
+            }
+
+            timed_out =
+                !sc_cond_timedwait(&db->wait_cond, &db->mutex, deadline);
+        }
+
+        bool stopped = db->stopped;
+        sc_mutex_unlock(&db->mutex);
+
+        if (stopped) {
+            sc_delayed_frame_destroy(&dframe);
+            goto stopped;
+        }
+
+#ifndef SC_BUFFERING_NDEBUG
+        LOGD("Buffering: %" PRItick ";%" PRItick ";%" PRItick,
+             pts, dframe.push_date, sc_tick_now());
+#endif
+
+        bool ok = sc_frame_source_sinks_push(&db->frame_source, dframe.frame);
+        sc_delayed_frame_destroy(&dframe);
+        if (!ok) {
+            LOGE("Delayed frame could not be pushed, stopping");
+            sc_mutex_lock(&db->mutex);
+            // Prevent to push any new frame
+            db->stopped = true;
+            sc_mutex_unlock(&db->mutex);
+            goto stopped;
+        }
+    }
+
+stopped:
+    assert(db->stopped);
+
+    // Flush queue
+    while (!sc_vecdeque_is_empty(&db->queue)) {
+        struct sc_delayed_frame *dframe = sc_vecdeque_popref(&db->queue);
+        sc_delayed_frame_destroy(dframe);
+    }
+
+    LOGD("Buffering thread ended");
+
+    return 0;
+}
+
+static bool
+sc_delay_buffer_frame_sink_open(struct sc_frame_sink *sink,
+                                const AVCodecContext *ctx) {
+    struct sc_delay_buffer *db = DOWNCAST(sink);
+    (void) ctx;
+
+    bool ok = sc_mutex_init(&db->mutex);
+    if (!ok) {
+        return false;
+    }
+
+    ok = sc_cond_init(&db->queue_cond);
+    if (!ok) {
+        goto error_destroy_mutex;
+    }
+
+    ok = sc_cond_init(&db->wait_cond);
+    if (!ok) {
+        goto error_destroy_queue_cond;
+    }
+
+    sc_clock_init(&db->clock);
+    sc_vecdeque_init(&db->queue);
+
+    if (!sc_frame_source_sinks_open(&db->frame_source, ctx)) {
+        goto error_destroy_wait_cond;
+    }
+
+    ok = sc_thread_create(&db->thread, run_buffering, "scrcpy-dbuf", db);
+    if (!ok) {
+        LOGE("Could not start buffering thread");
+        goto error_close_sinks;
+    }
+
+    return true;
+
+error_close_sinks:
+    sc_frame_source_sinks_close(&db->frame_source);
+error_destroy_wait_cond:
+    sc_cond_destroy(&db->wait_cond);
+error_destroy_queue_cond:
+    sc_cond_destroy(&db->queue_cond);
+error_destroy_mutex:
+    sc_mutex_destroy(&db->mutex);
+
+    return false;
+}
+
+static void
+sc_delay_buffer_frame_sink_close(struct sc_frame_sink *sink) {
+    struct sc_delay_buffer *db = DOWNCAST(sink);
+
+    sc_mutex_lock(&db->mutex);
+    db->stopped = true;
+    sc_cond_signal(&db->queue_cond);
+    sc_cond_signal(&db->wait_cond);
+    sc_mutex_unlock(&db->mutex);
+
+    sc_thread_join(&db->thread, NULL);
+
+    sc_frame_source_sinks_close(&db->frame_source);
+
+    sc_cond_destroy(&db->wait_cond);
+    sc_cond_destroy(&db->queue_cond);
+    sc_mutex_destroy(&db->mutex);
+}
+
+static bool
+sc_delay_buffer_frame_sink_push(struct sc_frame_sink *sink,
+                                const AVFrame *frame) {
+    struct sc_delay_buffer *db = DOWNCAST(sink);
+
+    sc_mutex_lock(&db->mutex);
+
+    if (db->stopped) {
+        sc_mutex_unlock(&db->mutex);
+        return false;
+    }
+
+    sc_tick pts = SC_TICK_FROM_US(frame->pts);
+    sc_clock_update(&db->clock, sc_tick_now(), pts);
+    sc_cond_signal(&db->wait_cond);
+
+    if (db->first_frame_asap && db->clock.count == 1) {
+        sc_mutex_unlock(&db->mutex);
+        return sc_frame_source_sinks_push(&db->frame_source, frame);
+    }
+
+    struct sc_delayed_frame dframe;
+    bool ok = sc_delayed_frame_init(&dframe, frame);
+    if (!ok) {
+        sc_mutex_unlock(&db->mutex);
+        return false;
+    }
+
+#ifndef SC_BUFFERING_NDEBUG
+    dframe.push_date = sc_tick_now();
+#endif
+
+    ok = sc_vecdeque_push(&db->queue, dframe);
+    if (!ok) {
+        sc_mutex_unlock(&db->mutex);
+        LOG_OOM();
+        return false;
+    }
+
+    sc_cond_signal(&db->queue_cond);
+
+    sc_mutex_unlock(&db->mutex);
+
+    return true;
+}
+
+void
+sc_delay_buffer_init(struct sc_delay_buffer *db, sc_tick delay,
+                     bool first_frame_asap) {
+    assert(delay > 0);
+
+    db->delay = delay;
+    db->first_frame_asap = first_frame_asap;
+
+    sc_frame_source_init(&db->frame_source);
+
+    static const struct sc_frame_sink_ops ops = {
+        .open = sc_delay_buffer_frame_sink_open,
+        .close = sc_delay_buffer_frame_sink_close,
+        .push = sc_delay_buffer_frame_sink_push,
+    };
+
+    db->frame_sink.ops = &ops;
+}

app/src/delay_buffer.h

@@ -0,0 +1,60 @@
+#ifndef SC_DELAY_BUFFER_H
+#define SC_DELAY_BUFFER_H
+
+#include "common.h"
+
+#include <stdbool.h>
+
+#include "clock.h"
+#include "trait/frame_source.h"
+#include "trait/frame_sink.h"
+#include "util/thread.h"
+#include "util/tick.h"
+#include "util/vecdeque.h"
+
+// forward declarations
+typedef struct AVFrame AVFrame;
+
+struct sc_delayed_frame {
+    AVFrame *frame;
+#ifndef NDEBUG
+    sc_tick push_date;
+#endif
+};
+
+struct sc_delayed_frame_queue SC_VECDEQUE(struct sc_delayed_frame);
+
+struct sc_delay_buffer {
+    struct sc_frame_source frame_source; // frame source trait
+    struct sc_frame_sink frame_sink; // frame sink trait
+
+    sc_tick delay;
+    bool first_frame_asap;
+
+    sc_thread thread;
+    sc_mutex mutex;
+    sc_cond queue_cond;
+    sc_cond wait_cond;
+
+    struct sc_clock clock;
+    struct sc_delayed_frame_queue queue;
+    bool stopped;
+};
+
+struct sc_delay_buffer_callbacks {
+    bool (*on_new_frame)(struct sc_delay_buffer *db, const AVFrame *frame,
+                         void *userdata);
+};
+
+/**
+ * Initialize a delay buffer.
+ *
+ * \param delay a (strictly) positive delay
+ * \param first_frame_asap if true, do not delay the first frame (useful for
+                           a video stream).
+ */
+void
+sc_delay_buffer_init(struct sc_delay_buffer *db, sc_tick delay,
+                     bool first_frame_asap);
+
+#endif

app/src/demuxer.c

@@ -1,6 +1,7 @@
 #include "demuxer.h"
 
 #include <assert.h>
+#include <libavutil/channel_layout.h>
 #include <libavutil/time.h>
 #include <unistd.h>
 
@@ -25,6 +26,7 @@ sc_demuxer_to_avcodec_id(uint32_t codec_id) {
 #define SC_CODEC_ID_AV1 UINT32_C(0x00617631) // "av1" in ASCII
 #define SC_CODEC_ID_OPUS UINT32_C(0x6f707573) // "opus" in ASCII
 #define SC_CODEC_ID_AAC UINT32_C(0x00616163) // "aac in ASCII"
+#define SC_CODEC_ID_RAW UINT32_C(0x00726177) // "raw" in ASCII
     switch (codec_id) {
         case SC_CODEC_ID_H264:
             return AV_CODEC_ID_H264;
@@ -36,6 +38,8 @@ sc_demuxer_to_avcodec_id(uint32_t codec_id) {
             return AV_CODEC_ID_OPUS;
         case SC_CODEC_ID_AAC:
             return AV_CODEC_ID_AAC;
+        case SC_CODEC_ID_RAW:
+            return AV_CODEC_ID_PCM_S16LE;
         default:
             LOGE("Unknown codec id 0x%08" PRIx32, codec_id);
             return AV_CODEC_ID_NONE;
@@ -54,6 +58,20 @@ sc_demuxer_recv_codec_id(struct sc_demuxer *demuxer, uint32_t *codec_id) {
     return true;
 }
 
+static bool
+sc_demuxer_recv_video_size(struct sc_demuxer *demuxer, uint32_t *width,
+                           uint32_t *height) {
+    uint8_t data[8];
+    ssize_t r = net_recv_all(demuxer->socket, data, 8);
+    if (r < 8) {
+        return false;
+    }
+
+    *width = sc_read32be(data);
+    *height = sc_read32be(data + 4);
+    return true;
+}
+
 static bool
 sc_demuxer_recv_packet(struct sc_demuxer *demuxer, AVPacket *packet) {
     // The video stream contains raw packets, without time information. When we
@@ -112,86 +130,26 @@ sc_demuxer_recv_packet(struct sc_demuxer *demuxer, AVPacket *packet) {
     return true;
 }
 
-static bool
-push_packet_to_sinks(struct sc_demuxer *demuxer, const AVPacket *packet) {
-    for (unsigned i = 0; i < demuxer->sink_count; ++i) {
-        struct sc_packet_sink *sink = demuxer->sinks[i];
-        if (!sink->ops->push(sink, packet)) {
-            return false;
-        }
-    }
-
-    return true;
-}
-
-static bool
-sc_demuxer_push_packet(struct sc_demuxer *demuxer, AVPacket *packet) {
-    bool ok = push_packet_to_sinks(demuxer, packet);
-    if (!ok) {
-        LOGE("Demuxer '%s': could not process packet", demuxer->name);
-        return false;
-    }
-
-    return true;
-}
-
-static void
-sc_demuxer_close_first_sinks(struct sc_demuxer *demuxer, unsigned count) {
-    while (count) {
-        struct sc_packet_sink *sink = demuxer->sinks[--count];
-        sink->ops->close(sink);
-    }
-}
-
-static inline void
-sc_demuxer_close_sinks(struct sc_demuxer *demuxer) {
-    sc_demuxer_close_first_sinks(demuxer, demuxer->sink_count);
-}
-
-static bool
-sc_demuxer_open_sinks(struct sc_demuxer *demuxer, const AVCodec *codec) {
-    for (unsigned i = 0; i < demuxer->sink_count; ++i) {
-        struct sc_packet_sink *sink = demuxer->sinks[i];
-        if (!sink->ops->open(sink, codec)) {
-            sc_demuxer_close_first_sinks(demuxer, i);
-            return false;
-        }
-    }
-
-    return true;
-}
-
-static void
-sc_demuxer_disable_sinks(struct sc_demuxer *demuxer) {
-    for (unsigned i = 0; i < demuxer->sink_count; ++i) {
-        struct sc_packet_sink *sink = demuxer->sinks[i];
-        if (sink->ops->disable) {
-            sink->ops->disable(sink);
-        }
-    }
-}
-
 static int
 run_demuxer(void *data) {
     struct sc_demuxer *demuxer = data;
 
     // Flag to report end-of-stream (i.e. device disconnected)
-    bool eos = false;
+    enum sc_demuxer_status status = SC_DEMUXER_STATUS_ERROR;
 
     uint32_t raw_codec_id;
     bool ok = sc_demuxer_recv_codec_id(demuxer, &raw_codec_id);
     if (!ok) {
         LOGE("Demuxer '%s': stream disabled due to connection error",
              demuxer->name);
-        eos = true;
         goto end;
     }
 
     if (raw_codec_id == 0) {
         LOGW("Demuxer '%s': stream explicitly disabled by the device",
              demuxer->name);
-        sc_demuxer_disable_sinks(demuxer);
-        eos = true;
+        sc_packet_source_sinks_disable(&demuxer->packet_source);
+        status = SC_DEMUXER_STATUS_DISABLED;
         goto end;
     }
 
@@ -205,7 +163,7 @@ run_demuxer(void *data) {
     if (codec_id == AV_CODEC_ID_NONE) {
         LOGE("Demuxer '%s': stream disabled due to unsupported codec",
              demuxer->name);
-        sc_demuxer_disable_sinks(demuxer);
+        sc_packet_source_sinks_disable(&demuxer->packet_source);
         goto end;
     }
 
@@ -213,14 +171,49 @@ run_demuxer(void *data) {
     if (!codec) {
         LOGE("Demuxer '%s': stream disabled due to missing decoder",
              demuxer->name);
-        sc_demuxer_disable_sinks(demuxer);
+        sc_packet_source_sinks_disable(&demuxer->packet_source);
         goto end;
     }
 
-    if (!sc_demuxer_open_sinks(demuxer, codec)) {
+    AVCodecContext *codec_ctx = avcodec_alloc_context3(codec);
+    if (!codec_ctx) {
+        LOG_OOM();
         goto end;
     }
 
+    codec_ctx->flags |= AV_CODEC_FLAG_LOW_DELAY;
+
+    if (codec->type == AVMEDIA_TYPE_VIDEO) {
+        uint32_t width;
+        uint32_t height;
+        ok = sc_demuxer_recv_video_size(demuxer, &width, &height);
+        if (!ok) {
+            goto finally_free_context;
+        }
+
+        codec_ctx->width = width;
+        codec_ctx->height = height;
+        codec_ctx->pix_fmt = AV_PIX_FMT_YUV420P;
+    } else {
+        // Hardcoded audio properties
+#ifdef SCRCPY_LAVU_HAS_CHLAYOUT
+        codec_ctx->ch_layout = (AVChannelLayout) AV_CHANNEL_LAYOUT_STEREO;
+#else
+        codec_ctx->channel_layout = AV_CH_LAYOUT_STEREO;
+        codec_ctx->channels = 2;
+#endif
+        codec_ctx->sample_rate = 48000;
+    }
+
+    if (avcodec_open2(codec_ctx, codec, NULL) < 0) {
+        LOGE("Demuxer '%s': could not open codec", demuxer->name);
+        goto finally_free_context;
+    }
+
+    if (!sc_packet_source_sinks_open(&demuxer->packet_source, codec_ctx)) {
+        goto finally_free_context;
+    }
+
     // Config packets must be merged with the next non-config packet only for
     // video streams
     bool must_merge_config_packet = codec->type == AVMEDIA_TYPE_VIDEO;
@@ -241,7 +234,7 @@ run_demuxer(void *data) {
         bool ok = sc_demuxer_recv_packet(demuxer, packet);
         if (!ok) {
             // end of stream
-            eos = true;
+            status = SC_DEMUXER_STATUS_EOS;
             break;
         }
 
@@ -254,10 +247,10 @@ run_demuxer(void *data) {
             }
         }
 
-        ok = sc_demuxer_push_packet(demuxer, packet);
+        ok = sc_packet_source_sinks_push(&demuxer->packet_source, packet);
         av_packet_unref(packet);
         if (!ok) {
-            // cannot process packet (error already logged)
+            // The sink already logged its concrete error
             break;
         }
     }
@@ -270,9 +263,12 @@ run_demuxer(void *data) {
 
     av_packet_free(&packet);
 finally_close_sinks:
-    sc_demuxer_close_sinks(demuxer);
+    sc_packet_source_sinks_close(&demuxer->packet_source);
+finally_free_context:
+    // This also calls avcodec_close() internally
+    avcodec_free_context(&codec_ctx);
 end:
-    demuxer->cbs->on_ended(demuxer, eos, demuxer->cbs_userdata);
+    demuxer->cbs->on_ended(demuxer, status, demuxer->cbs_userdata);
 
     return 0;
 }
@@ -284,7 +280,7 @@ sc_demuxer_init(struct sc_demuxer *demuxer, const char *name, sc_socket socket,
 
     demuxer->name = name; // statically allocated
     demuxer->socket = socket;
-    demuxer->sink_count = 0;
+    sc_packet_source_init(&demuxer->packet_source);
 
     assert(cbs && cbs->on_ended);
 
@@ -292,14 +288,6 @@ sc_demuxer_init(struct sc_demuxer *demuxer, const char *name, sc_socket socket,
     demuxer->cbs_userdata = cbs_userdata;
 }
 
-void
-sc_demuxer_add_sink(struct sc_demuxer *demuxer, struct sc_packet_sink *sink) {
-    assert(demuxer->sink_count < SC_DEMUXER_MAX_SINKS);
-    assert(sink);
-    assert(sink->ops);
-    demuxer->sinks[demuxer->sink_count++] = sink;
-}
-
 bool
 sc_demuxer_start(struct sc_demuxer *demuxer) {
     LOGD("Demuxer '%s': starting thread", demuxer->name);

app/src/demuxer.h

@@ -8,27 +8,32 @@
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
 
+#include "trait/packet_source.h"
 #include "trait/packet_sink.h"
 #include "util/net.h"
 #include "util/thread.h"
 
-#define SC_DEMUXER_MAX_SINKS 2
-
 struct sc_demuxer {
+    struct sc_packet_source packet_source; // packet source trait
+
     const char *name; // must be statically allocated (e.g. a string literal)
 
     sc_socket socket;
     sc_thread thread;
 
-    struct sc_packet_sink *sinks[SC_DEMUXER_MAX_SINKS];
-    unsigned sink_count;
-
     const struct sc_demuxer_callbacks *cbs;
     void *cbs_userdata;
 };
 
+enum sc_demuxer_status {
+    SC_DEMUXER_STATUS_EOS,
+    SC_DEMUXER_STATUS_DISABLED,
+    SC_DEMUXER_STATUS_ERROR,
+};
+
 struct sc_demuxer_callbacks {
-    void (*on_ended)(struct sc_demuxer *demuxer, bool eos, void *userdata);
+    void (*on_ended)(struct sc_demuxer *demuxer, enum sc_demuxer_status,
+                     void *userdata);
 };
 
 // The name must be statically allocated (e.g. a string literal)
@@ -36,9 +41,6 @@ void
 sc_demuxer_init(struct sc_demuxer *demuxer, const char *name, sc_socket socket,
                 const struct sc_demuxer_callbacks *cbs, void *cbs_userdata);
 
-void
-sc_demuxer_add_sink(struct sc_demuxer *demuxer, struct sc_packet_sink *sink);
-
 bool
 sc_demuxer_start(struct sc_demuxer *demuxer);
 

app/src/events.h

@@ -5,3 +5,4 @@
 #define SC_EVENT_USB_DEVICE_DISCONNECTED  (SDL_USEREVENT + 4)
 #define SC_EVENT_DEMUXER_ERROR            (SDL_USEREVENT + 5)
 #define SC_EVENT_RECORDER_ERROR           (SDL_USEREVENT + 6)
+#define SC_EVENT_SCREEN_INIT_SIZE         (SDL_USEREVENT + 7)

app/src/file_pusher.c

@@ -19,7 +19,7 @@ sc_file_pusher_init(struct sc_file_pusher *fp, const char *serial,
                     const char *push_target) {
     assert(serial);
 
-    cbuf_init(&fp->queue);
+    sc_vecdeque_init(&fp->queue);
 
     bool ok = sc_mutex_init(&fp->mutex);
     if (!ok) {
@@ -65,9 +65,10 @@ sc_file_pusher_destroy(struct sc_file_pusher *fp) {
     sc_intr_destroy(&fp->intr);
     free(fp->serial);
 
-    struct sc_file_pusher_request req;
-    while (cbuf_take(&fp->queue, &req)) {
-        sc_file_pusher_request_destroy(&req);
+    while (!sc_vecdeque_is_empty(&fp->queue)) {
+        struct sc_file_pusher_request *req = sc_vecdeque_popref(&fp->queue);
+        assert(req);
+        sc_file_pusher_request_destroy(req);
     }
 }
 
@@ -91,13 +92,20 @@ sc_file_pusher_request(struct sc_file_pusher *fp,
     };
 
     sc_mutex_lock(&fp->mutex);
-    bool was_empty = cbuf_is_empty(&fp->queue);
-    bool res = cbuf_push(&fp->queue, req);
+    bool was_empty = sc_vecdeque_is_empty(&fp->queue);
+    bool res = sc_vecdeque_push(&fp->queue, req);
+    if (!res) {
+        LOG_OOM();
+        sc_mutex_unlock(&fp->mutex);
+        return false;
+    }
+
     if (was_empty) {
         sc_cond_signal(&fp->event_cond);
     }
     sc_mutex_unlock(&fp->mutex);
-    return res;
+
+    return true;
 }
 
 static int
@@ -113,7 +121,7 @@ run_file_pusher(void *data) {
 
     for (;;) {
         sc_mutex_lock(&fp->mutex);
-        while (!fp->stopped && cbuf_is_empty(&fp->queue)) {
+        while (!fp->stopped && sc_vecdeque_is_empty(&fp->queue)) {
             sc_cond_wait(&fp->event_cond, &fp->mutex);
         }
         if (fp->stopped) {
@@ -121,10 +129,9 @@ run_file_pusher(void *data) {
             sc_mutex_unlock(&fp->mutex);
             break;
         }
-        struct sc_file_pusher_request req;
-        bool non_empty = cbuf_take(&fp->queue, &req);
-        assert(non_empty);
-        (void) non_empty;
+
+        assert(!sc_vecdeque_is_empty(&fp->queue));
+        struct sc_file_pusher_request req = sc_vecdeque_pop(&fp->queue);
         sc_mutex_unlock(&fp->mutex);
 
         if (req.action == SC_FILE_PUSHER_ACTION_INSTALL_APK) {
@@ -165,14 +172,18 @@ sc_file_pusher_start(struct sc_file_pusher *fp) {
 
 void
 sc_file_pusher_stop(struct sc_file_pusher *fp) {
-    sc_mutex_lock(&fp->mutex);
-    fp->stopped = true;
-    sc_cond_signal(&fp->event_cond);
-    sc_intr_interrupt(&fp->intr);
-    sc_mutex_unlock(&fp->mutex);
+    if (fp->initialized) {
+        sc_mutex_lock(&fp->mutex);
+        fp->stopped = true;
+        sc_cond_signal(&fp->event_cond);
+        sc_intr_interrupt(&fp->intr);
+        sc_mutex_unlock(&fp->mutex);
+    }
 }
 
 void
 sc_file_pusher_join(struct sc_file_pusher *fp) {
-    sc_thread_join(&fp->thread, NULL);
+    if (fp->initialized) {
+        sc_thread_join(&fp->thread, NULL);
+    }
 }

app/src/file_pusher.h

@@ -5,9 +5,9 @@
 
 #include <stdbool.h>
 
-#include "util/cbuf.h"
-#include "util/thread.h"
 #include "util/intr.h"
+#include "util/thread.h"
+#include "util/vecdeque.h"
 
 enum sc_file_pusher_action {
     SC_FILE_PUSHER_ACTION_INSTALL_APK,
@@ -19,7 +19,7 @@ struct sc_file_pusher_request {
     char *file;
 };
 
-struct sc_file_pusher_request_queue CBUF(struct sc_file_pusher_request, 16);
+struct sc_file_pusher_request_queue SC_VECDEQUE(struct sc_file_pusher_request);
 
 struct sc_file_pusher {
     char *serial;

app/src/fps_counter.c

@@ -96,6 +96,7 @@ run_fps_counter(void *data) {
 bool
 sc_fps_counter_start(struct sc_fps_counter *counter) {
     sc_mutex_lock(&counter->mutex);
+    counter->interrupted = false;
     counter->next_timestamp = sc_tick_now() + SC_FPS_COUNTER_INTERVAL;
     counter->nr_rendered = 0;
     counter->nr_skipped = 0;

app/src/options.c

@@ -43,6 +43,8 @@ const struct scrcpy_options scrcpy_options_default = {
     .display_id = 0,
     .display_buffer = 0,
     .v4l2_buffer = 0,
+    .audio_buffer = SC_TICK_FROM_MS(50),
+    .audio_output_buffer = SC_TICK_FROM_MS(5),
 #ifdef HAVE_USB
     .otg = false,
 #endif
@@ -72,6 +74,7 @@ const struct scrcpy_options scrcpy_options_default = {
     .start_fps_counter = false,
     .power_on = true,
     .audio = true,
+    .require_audio = false,
     .list_encoders = false,
     .list_displays = false,
 };

app/src/options.h

@@ -29,6 +29,7 @@ enum sc_codec {
     SC_CODEC_AV1,
     SC_CODEC_OPUS,
     SC_CODEC_AAC,
+    SC_CODEC_RAW,
 };
 
 enum sc_lock_video_orientation {
@@ -125,6 +126,8 @@ struct scrcpy_options {
     uint32_t display_id;
     sc_tick display_buffer;
     sc_tick v4l2_buffer;
+    sc_tick audio_buffer;
+    sc_tick audio_output_buffer;
 #ifdef HAVE_USB
     bool otg;
 #endif
@@ -154,6 +157,7 @@ struct scrcpy_options {
     bool start_fps_counter;
     bool power_on;
     bool audio;
+    bool require_audio;
     bool list_encoders;
     bool list_displays;
 };

app/src/recorder.c

@@ -33,41 +33,27 @@ find_muxer(const char *name) {
     return oformat;
 }
 
-static struct sc_record_packet *
-sc_record_packet_new(const AVPacket *packet) {
-    struct sc_record_packet *rec = malloc(sizeof(*rec));
-    if (!rec) {
+static AVPacket *
+sc_recorder_packet_ref(const AVPacket *packet) {
+    AVPacket *p = av_packet_alloc();
+    if (!p) {
         LOG_OOM();
         return NULL;
     }
 
-    rec->packet = av_packet_alloc();
-    if (!rec->packet) {
-        LOG_OOM();
-        free(rec);
+    if (av_packet_ref(p, packet)) {
+        av_packet_free(&p);
         return NULL;
     }
 
-    if (av_packet_ref(rec->packet, packet)) {
-        av_packet_free(&rec->packet);
-        free(rec);
-        return NULL;
-    }
-    return rec;
-}
-
-static void
-sc_record_packet_delete(struct sc_record_packet *rec) {
-    av_packet_free(&rec->packet);
-    free(rec);
+    return p;
 }
 
 static void
 sc_recorder_queue_clear(struct sc_recorder_queue *queue) {
-    while (!sc_queue_is_empty(queue)) {
-        struct sc_record_packet *rec;
-        sc_queue_take(queue, next, &rec);
-        sc_record_packet_delete(rec);
+    while (!sc_vecdeque_is_empty(queue)) {
+        AVPacket *p = sc_vecdeque_pop(queue);
+        av_packet_free(&p);
     }
 }
 
@@ -164,80 +150,14 @@ sc_recorder_close_output_file(struct sc_recorder *recorder) {
     avformat_free_context(recorder->ctx);
 }
 
-static bool
-sc_recorder_wait_video_stream(struct sc_recorder *recorder) {
-    sc_mutex_lock(&recorder->mutex);
-    while (!recorder->video_codec && !recorder->stopped) {
-        sc_cond_wait(&recorder->stream_cond, &recorder->mutex);
-    }
-    const AVCodec *codec = recorder->video_codec;
-    sc_mutex_unlock(&recorder->mutex);
-
-    if (codec) {
-        AVStream *stream = avformat_new_stream(recorder->ctx, codec);
-        if (!stream) {
-            return false;
-        }
-
-        stream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
-        stream->codecpar->codec_id = codec->id;
-        stream->codecpar->format = AV_PIX_FMT_YUV420P;
-        stream->codecpar->width = recorder->declared_frame_size.width;
-        stream->codecpar->height = recorder->declared_frame_size.height;
-
-        recorder->video_stream_index = stream->index;
-    }
-
-    return true;
-}
-
-static bool
-sc_recorder_wait_audio_stream(struct sc_recorder *recorder) {
-    sc_mutex_lock(&recorder->mutex);
-    while (!recorder->audio_codec && !recorder->audio_disabled
-            && !recorder->stopped) {
-        sc_cond_wait(&recorder->stream_cond, &recorder->mutex);
-    }
-
-    if (recorder->audio_disabled) {
-        // Reset audio flag. From there, the recorder thread may access this
-        // flag without any mutex.
-        recorder->audio = false;
-    }
-
-    const AVCodec *codec = recorder->audio_codec;
-    sc_mutex_unlock(&recorder->mutex);
-
-    if (codec) {
-        AVStream *stream = avformat_new_stream(recorder->ctx, codec);
-        if (!stream) {
-            return false;
-        }
-
-        stream->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
-        stream->codecpar->codec_id = codec->id;
-#ifdef SCRCPY_LAVU_HAS_CHLAYOUT
-        stream->codecpar->ch_layout.nb_channels = 2;
-#else
-        stream->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
-        stream->codecpar->channels = 2;
-#endif
-        stream->codecpar->sample_rate = 48000;
-
-        recorder->audio_stream_index = stream->index;
-    }
-
-    return true;
-}
-
 static inline bool
 sc_recorder_has_empty_queues(struct sc_recorder *recorder) {
-    if (sc_queue_is_empty(&recorder->video_queue)) {
+    if (sc_vecdeque_is_empty(&recorder->video_queue)) {
         // The video queue is empty
         return true;
     }
 
-    if (recorder->audio && sc_queue_is_empty(&recorder->audio_queue)) {
+    if (recorder->audio && sc_vecdeque_is_empty(&recorder->audio_queue)) {
         // The audio queue is empty (when audio is enabled)
         return true;
     }
@@ -250,31 +170,33 @@ static bool
 sc_recorder_process_header(struct sc_recorder *recorder) {
     sc_mutex_lock(&recorder->mutex);
 
-    while (!recorder->stopped && sc_recorder_has_empty_queues(recorder)) {
-        sc_cond_wait(&recorder->queue_cond, &recorder->mutex);
+    while (!recorder->stopped && (!recorder->video_init
+                               || !recorder->audio_init
+                               || sc_recorder_has_empty_queues(recorder))) {
+        sc_cond_wait(&recorder->stream_cond, &recorder->mutex);
     }
 
-    if (recorder->stopped && sc_queue_is_empty(&recorder->video_queue)) {
+    if (sc_vecdeque_is_empty(&recorder->video_queue)) {
+        assert(recorder->stopped);
         // If the recorder is stopped, don't process anything if there are not
         // at least video packets
         sc_mutex_unlock(&recorder->mutex);
         return false;
     }
 
-    struct sc_record_packet *video_pkt;
-    sc_queue_take(&recorder->video_queue, next, &video_pkt);
+    AVPacket *video_pkt = sc_vecdeque_pop(&recorder->video_queue);
 
-    struct sc_record_packet *audio_pkt = NULL;
-    if (!sc_queue_is_empty(&recorder->audio_queue)) {
+    AVPacket *audio_pkt = NULL;
+    if (!sc_vecdeque_is_empty(&recorder->audio_queue)) {
         assert(recorder->audio);
-        sc_queue_take(&recorder->audio_queue, next, &audio_pkt);
+        audio_pkt = sc_vecdeque_pop(&recorder->audio_queue);
     }
 
     sc_mutex_unlock(&recorder->mutex);
 
     int ret = false;
 
-    if (video_pkt->packet->pts != AV_NOPTS_VALUE) {
+    if (video_pkt->pts != AV_NOPTS_VALUE) {
         LOGE("The first video packet is not a config packet");
         goto end;
     }
@@ -282,13 +204,13 @@ sc_recorder_process_header(struct sc_recorder *recorder) {
     assert(recorder->video_stream_index >= 0);
     AVStream *video_stream =
         recorder->ctx->streams[recorder->video_stream_index];
-    bool ok = sc_recorder_set_extradata(video_stream, video_pkt->packet);
+    bool ok = sc_recorder_set_extradata(video_stream, video_pkt);
     if (!ok) {
         goto end;
     }
 
     if (audio_pkt) {
-        if (audio_pkt->packet->pts != AV_NOPTS_VALUE) {
+        if (audio_pkt->pts != AV_NOPTS_VALUE) {
             LOGE("The first audio packet is not a config packet");
             goto end;
         }
@@ -296,7 +218,7 @@ sc_recorder_process_header(struct sc_recorder *recorder) {
         assert(recorder->audio_stream_index >= 0);
         AVStream *audio_stream =
             recorder->ctx->streams[recorder->audio_stream_index];
-        ok = sc_recorder_set_extradata(audio_stream, audio_pkt->packet);
+        ok = sc_recorder_set_extradata(audio_stream, audio_pkt);
         if (!ok) {
             goto end;
         }
@@ -311,9 +233,9 @@ sc_recorder_process_header(struct sc_recorder *recorder) {
     ret = true;
 
 end:
-    sc_record_packet_delete(video_pkt);
+    av_packet_free(&video_pkt);
     if (audio_pkt) {
-        sc_record_packet_delete(audio_pkt);
+        av_packet_free(&audio_pkt);
     }
 
     return ret;
@@ -328,12 +250,12 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
         return false;
     }
 
-    struct sc_record_packet *video_pkt = NULL;
-    struct sc_record_packet *audio_pkt = NULL;
+    AVPacket *video_pkt = NULL;
+    AVPacket *audio_pkt = NULL;
 
     // We can write a video packet only once we received the next one so that
     // we can set its duration (next_pts - current_pts)
-    struct sc_record_packet *video_pkt_previous = NULL;
+    AVPacket *video_pkt_previous = NULL;
 
     bool error = false;
 
@@ -341,12 +263,12 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
         sc_mutex_lock(&recorder->mutex);
 
         while (!recorder->stopped) {
-            if (!video_pkt && !sc_queue_is_empty(&recorder->video_queue)) {
+            if (!video_pkt && !sc_vecdeque_is_empty(&recorder->video_queue)) {
                 // A new packet may be assigned to video_pkt and be processed
                 break;
             }
             if (recorder->audio && !audio_pkt
-                    && !sc_queue_is_empty(&recorder->audio_queue)) {
+                    && !sc_vecdeque_is_empty(&recorder->audio_queue)) {
                 // A new packet may be assigned to audio_pkt and be processed
                 break;
             }
@@ -358,20 +280,20 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
 
         // If there is no audio, then the audio_queue will remain empty forever
         // and audio_pkt will always be NULL.
-        assert(recorder->audio
-                || (!audio_pkt && sc_queue_is_empty(&recorder->audio_queue)));
+        assert(recorder->audio || (!audio_pkt
+                && sc_vecdeque_is_empty(&recorder->audio_queue)));
 
-        if (!video_pkt && !sc_queue_is_empty(&recorder->video_queue)) {
-            sc_queue_take(&recorder->video_queue, next, &video_pkt);
+        if (!video_pkt && !sc_vecdeque_is_empty(&recorder->video_queue)) {
+            video_pkt = sc_vecdeque_pop(&recorder->video_queue);
         }
 
-        if (!audio_pkt && !sc_queue_is_empty(&recorder->audio_queue)) {
-            sc_queue_take(&recorder->audio_queue, next, &audio_pkt);
+        if (!audio_pkt && !sc_vecdeque_is_empty(&recorder->audio_queue)) {
+            audio_pkt = sc_vecdeque_pop(&recorder->audio_queue);
         }
 
         if (recorder->stopped && !video_pkt && !audio_pkt) {
-            assert(sc_queue_is_empty(&recorder->video_queue));
-            assert(sc_queue_is_empty(&recorder->audio_queue));
+            assert(sc_vecdeque_is_empty(&recorder->video_queue));
+            assert(sc_vecdeque_is_empty(&recorder->audio_queue));
             sc_mutex_unlock(&recorder->mutex);
             break;
         }
@@ -383,38 +305,32 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
         // Ignore further config packets (e.g. on device orientation
         // change). The next non-config packet will have the config packet
         // data prepended.
-        if (video_pkt && video_pkt->packet->pts == AV_NOPTS_VALUE) {
-            sc_record_packet_delete(video_pkt);
+        if (video_pkt && video_pkt->pts == AV_NOPTS_VALUE) {
+            av_packet_free(&video_pkt);
             video_pkt = NULL;
         }
 
-        if (audio_pkt && audio_pkt->packet->pts == AV_NOPTS_VALUE) {
-            sc_record_packet_delete(audio_pkt);
-            audio_pkt= NULL;
+        if (audio_pkt && audio_pkt->pts == AV_NOPTS_VALUE) {
+            av_packet_free(&audio_pkt);
+            audio_pkt = NULL;
         }
 
         if (pts_origin == AV_NOPTS_VALUE) {
             if (!recorder->audio) {
                 assert(video_pkt);
-                pts_origin = video_pkt->packet->pts;
+                pts_origin = video_pkt->pts;
             } else if (video_pkt && audio_pkt) {
-                pts_origin =
-                    MIN(video_pkt->packet->pts, audio_pkt->packet->pts);
+                pts_origin = MIN(video_pkt->pts, audio_pkt->pts);
             } else if (recorder->stopped) {
                 if (video_pkt) {
                     // The recorder is stopped without audio, record the video
                     // packets
-                    pts_origin = video_pkt->packet->pts;
+                    pts_origin = video_pkt->pts;
                 } else {
                     // Fail if there is no video
                     error = true;
                     goto end;
                 }
-                // If the recorder is stopped while one of the streams has no
-                // packets, then we must avoid a live-loop and correctly record
-                // the stream having packets.
-                pts_origin = video_pkt ? video_pkt->packet->pts
-                                       : audio_pkt->packet->pts;
             } else {
                 // We need both video and audio packets to initialize pts_origin
                 continue;
@@ -424,17 +340,16 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
         assert(pts_origin != AV_NOPTS_VALUE);
 
         if (video_pkt) {
-            video_pkt->packet->pts -= pts_origin;
-            video_pkt->packet->dts = video_pkt->packet->pts;
+            video_pkt->pts -= pts_origin;
+            video_pkt->dts = video_pkt->pts;
 
             if (video_pkt_previous) {
                 // we now know the duration of the previous packet
-                video_pkt_previous->packet->duration =
-                    video_pkt->packet->pts - video_pkt_previous->packet->pts;
+                video_pkt_previous->duration = video_pkt->pts
+                                             - video_pkt_previous->pts;
 
-                bool ok = sc_recorder_write_video(recorder,
-                                                  video_pkt_previous->packet);
-                sc_record_packet_delete(video_pkt_previous);
+                bool ok = sc_recorder_write_video(recorder, video_pkt_previous);
+                av_packet_free(&video_pkt_previous);
                 if (!ok) {
                     LOGE("Could not record video packet");
                     error = true;
@@ -447,34 +362,34 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
         }
 
         if (audio_pkt) {
-            audio_pkt->packet->pts -= pts_origin;
-            audio_pkt->packet->dts = audio_pkt->packet->pts;
+            audio_pkt->pts -= pts_origin;
+            audio_pkt->dts = audio_pkt->pts;
 
-            bool ok = sc_recorder_write_audio(recorder, audio_pkt->packet);
+            bool ok = sc_recorder_write_audio(recorder, audio_pkt);
             if (!ok) {
                 LOGE("Could not record audio packet");
                 error = true;
                 goto end;
             }
 
-            sc_record_packet_delete(audio_pkt);
+            av_packet_free(&audio_pkt);
             audio_pkt = NULL;
         }
     }
 
     // Write the last video packet
-    struct sc_record_packet *last = video_pkt_previous;
+    AVPacket *last = video_pkt_previous;
     if (last) {
         // assign an arbitrary duration to the last packet
-        last->packet->duration = 100000;
-        bool ok = sc_recorder_write_video(recorder, last->packet);
+        last->duration = 100000;
+        bool ok = sc_recorder_write_video(recorder, last);
         if (!ok) {
             // failing to write the last frame is not very serious, no
             // future frame may depend on it, so the resulting file
             // will still be valid
             LOGW("Could not record last packet");
         }
-        sc_record_packet_delete(last);
+        av_packet_free(&last);
     }
 
     int ret = av_write_trailer(recorder->ctx);
@@ -485,10 +400,10 @@ sc_recorder_process_packets(struct sc_recorder *recorder) {
 
 end:
     if (video_pkt) {
-        sc_record_packet_delete(video_pkt);
+        av_packet_free(&video_pkt);
     }
     if (audio_pkt) {
-        sc_record_packet_delete(audio_pkt);
+        av_packet_free(&audio_pkt);
     }
 
     return !error;
@@ -501,22 +416,6 @@ sc_recorder_record(struct sc_recorder *recorder) {
         return false;
     }
 
-    ok = sc_recorder_wait_video_stream(recorder);
-    if (!ok) {
-        sc_recorder_close_output_file(recorder);
-        return false;
-    }
-
-    if (recorder->audio) {
-        ok = sc_recorder_wait_audio_stream(recorder);
-        if (!ok) {
-            sc_recorder_close_output_file(recorder);
-            return false;
-        }
-    }
-
-    // If recorder->stopped, process any queued packet anyway
-
     ok = sc_recorder_process_packets(recorder);
     sc_recorder_close_output_file(recorder);
     return ok;
@@ -526,6 +425,10 @@ static int
 run_recorder(void *data) {
     struct sc_recorder *recorder = data;
 
+    // Recording is a background task
+    bool ok = sc_thread_set_priority(SC_THREAD_PRIORITY_LOW);
+    (void) ok; // We don't care if it worked
+
     bool success = sc_recorder_record(recorder);
 
     sc_mutex_lock(&recorder->mutex);
@@ -533,6 +436,7 @@ run_recorder(void *data) {
     recorder->stopped = true;
     // Discard pending packets
     sc_recorder_queue_clear(&recorder->video_queue);
+    sc_recorder_queue_clear(&recorder->audio_queue);
     sc_mutex_unlock(&recorder->mutex);
 
     if (success) {
@@ -552,9 +456,10 @@ run_recorder(void *data) {
 
 static bool
 sc_recorder_video_packet_sink_open(struct sc_packet_sink *sink,
-                                   const AVCodec *codec) {
+                                   AVCodecContext *ctx) {
     struct sc_recorder *recorder = DOWNCAST_VIDEO(sink);
-    assert(codec);
+    // only written from this thread, no need to lock
+    assert(!recorder->video_init);
 
     sc_mutex_lock(&recorder->mutex);
     if (recorder->stopped) {
@@ -562,7 +467,21 @@ sc_recorder_video_packet_sink_open(struct sc_packet_sink *sink,
         return false;
     }
 
-    recorder->video_codec = codec;
+    AVStream *stream = avformat_new_stream(recorder->ctx, ctx->codec);
+    if (!stream) {
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
+
+    int r = avcodec_parameters_from_context(stream->codecpar, ctx);
+    if (r < 0) {
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
+
+    recorder->video_stream_index = stream->index;
+
+    recorder->video_init = true;
     sc_cond_signal(&recorder->stream_cond);
     sc_mutex_unlock(&recorder->mutex);
 
@@ -572,6 +491,8 @@ sc_recorder_video_packet_sink_open(struct sc_packet_sink *sink,
 static void
 sc_recorder_video_packet_sink_close(struct sc_packet_sink *sink) {
     struct sc_recorder *recorder = DOWNCAST_VIDEO(sink);
+    // only written from this thread, no need to lock
+    assert(recorder->video_init);
 
     sc_mutex_lock(&recorder->mutex);
     // EOS also stops the recorder
@@ -584,6 +505,8 @@ static bool
 sc_recorder_video_packet_sink_push(struct sc_packet_sink *sink,
                                    const AVPacket *packet) {
     struct sc_recorder *recorder = DOWNCAST_VIDEO(sink);
+    // only written from this thread, no need to lock
+    assert(recorder->video_init);
 
     sc_mutex_lock(&recorder->mutex);
 
@@ -593,16 +516,22 @@ sc_recorder_video_packet_sink_push(struct sc_packet_sink *sink,
         return false;
     }
 
-    struct sc_record_packet *rec = sc_record_packet_new(packet);
+    AVPacket *rec = sc_recorder_packet_ref(packet);
     if (!rec) {
         LOG_OOM();
         sc_mutex_unlock(&recorder->mutex);
         return false;
     }
 
-    rec->packet->stream_index = 0;
+    rec->stream_index = recorder->video_stream_index;
+
+    bool ok = sc_vecdeque_push(&recorder->video_queue, rec);
+    if (!ok) {
+        LOG_OOM();
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
 
-    sc_queue_push(&recorder->video_queue, next, rec);
     sc_cond_signal(&recorder->queue_cond);
 
     sc_mutex_unlock(&recorder->mutex);
@@ -611,15 +540,29 @@ sc_recorder_video_packet_sink_push(struct sc_packet_sink *sink,
 
 static bool
 sc_recorder_audio_packet_sink_open(struct sc_packet_sink *sink,
-                                   const AVCodec *codec) {
+                                   AVCodecContext *ctx) {
     struct sc_recorder *recorder = DOWNCAST_AUDIO(sink);
     assert(recorder->audio);
     // only written from this thread, no need to lock
-    assert(!recorder->audio_disabled);
-    assert(codec);
+    assert(!recorder->audio_init);
 
     sc_mutex_lock(&recorder->mutex);
-    recorder->audio_codec = codec;
+
+    AVStream *stream = avformat_new_stream(recorder->ctx, ctx->codec);
+    if (!stream) {
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
+
+    int r = avcodec_parameters_from_context(stream->codecpar, ctx);
+    if (r < 0) {
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
+
+    recorder->audio_stream_index = stream->index;
+
+    recorder->audio_init = true;
     sc_cond_signal(&recorder->stream_cond);
     sc_mutex_unlock(&recorder->mutex);
 
@@ -631,7 +574,7 @@ sc_recorder_audio_packet_sink_close(struct sc_packet_sink *sink) {
     struct sc_recorder *recorder = DOWNCAST_AUDIO(sink);
     assert(recorder->audio);
     // only written from this thread, no need to lock
-    assert(!recorder->audio_disabled);
+    assert(recorder->audio_init);
 
     sc_mutex_lock(&recorder->mutex);
     // EOS also stops the recorder
@@ -646,7 +589,7 @@ sc_recorder_audio_packet_sink_push(struct sc_packet_sink *sink,
     struct sc_recorder *recorder = DOWNCAST_AUDIO(sink);
     assert(recorder->audio);
     // only written from this thread, no need to lock
-    assert(!recorder->audio_disabled);
+    assert(recorder->audio_init);
 
     sc_mutex_lock(&recorder->mutex);
 
@@ -656,16 +599,22 @@ sc_recorder_audio_packet_sink_push(struct sc_packet_sink *sink,
         return false;
     }
 
-    struct sc_record_packet *rec = sc_record_packet_new(packet);
+    AVPacket *rec = sc_recorder_packet_ref(packet);
     if (!rec) {
         LOG_OOM();
         sc_mutex_unlock(&recorder->mutex);
         return false;
     }
 
-    rec->packet->stream_index = 1;
+    rec->stream_index = recorder->audio_stream_index;
+
+    bool ok = sc_vecdeque_push(&recorder->audio_queue, rec);
+    if (!ok) {
+        LOG_OOM();
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
 
-    sc_queue_push(&recorder->audio_queue, next, rec);
     sc_cond_signal(&recorder->queue_cond);
 
     sc_mutex_unlock(&recorder->mutex);
@@ -677,13 +626,13 @@ sc_recorder_audio_packet_sink_disable(struct sc_packet_sink *sink) {
     struct sc_recorder *recorder = DOWNCAST_AUDIO(sink);
     assert(recorder->audio);
     // only written from this thread, no need to lock
-    assert(!recorder->audio_disabled);
-    assert(!recorder->audio_codec);
+    assert(!recorder->audio_init);
 
     LOGW("Audio stream recording disabled");
 
     sc_mutex_lock(&recorder->mutex);
-    recorder->audio_disabled = true;
+    recorder->audio = false;
+    recorder->audio_init = true;
     sc_cond_signal(&recorder->stream_cond);
     sc_mutex_unlock(&recorder->mutex);
 }
@@ -691,7 +640,6 @@ sc_recorder_audio_packet_sink_disable(struct sc_packet_sink *sink) {
 bool
 sc_recorder_init(struct sc_recorder *recorder, const char *filename,
                  enum sc_record_format format, bool audio,
-                 struct sc_size declared_frame_size,
                  const struct sc_recorder_callbacks *cbs, void *cbs_userdata) {
     recorder->filename = strdup(filename);
     if (!recorder->filename) {
@@ -716,19 +664,17 @@ sc_recorder_init(struct sc_recorder *recorder, const char *filename,
 
     recorder->audio = audio;
 
-    sc_queue_init(&recorder->video_queue);
-    sc_queue_init(&recorder->audio_queue);
+    sc_vecdeque_init(&recorder->video_queue);
+    sc_vecdeque_init(&recorder->audio_queue);
     recorder->stopped = false;
 
-    recorder->video_codec = NULL;
-    recorder->audio_codec = NULL;
-    recorder->audio_disabled = false;
+    recorder->video_init = false;
+    recorder->audio_init = false;
 
     recorder->video_stream_index = -1;
     recorder->audio_stream_index = -1;
 
     recorder->format = format;
-    recorder->declared_frame_size = declared_frame_size;
 
     assert(cbs && cbs->on_ended);
     recorder->cbs = cbs;

app/src/recorder.h

@@ -9,15 +9,10 @@
 #include "coords.h"
 #include "options.h"
 #include "trait/packet_sink.h"
-#include "util/queue.h"
 #include "util/thread.h"
+#include "util/vecdeque.h"
 
-struct sc_record_packet {
-    AVPacket *packet;
-    struct sc_record_packet *next;
-};
-
-struct sc_recorder_queue SC_QUEUE(struct sc_record_packet);
+struct sc_recorder_queue SC_VECDEQUE(AVPacket *);
 
 struct sc_recorder {
     struct sc_packet_sink video_packet_sink;
@@ -36,7 +31,6 @@ struct sc_recorder {
     char *filename;
     enum sc_record_format format;
     AVFormatContext *ctx;
-    struct sc_size declared_frame_size;
 
     sc_thread thread;
     sc_mutex mutex;
@@ -48,11 +42,8 @@ struct sc_recorder {
 
     // wake up the recorder thread once the video or audio codec is known
     sc_cond stream_cond;
-    const AVCodec *video_codec;
-    const AVCodec *audio_codec;
-    // Instead of providing an audio_codec, the demuxer may notify that the
-    // stream is disabled if the device could not capture audio
-    bool audio_disabled;
+    bool video_init;
+    bool audio_init;
 
     int video_stream_index;
     int audio_stream_index;
@@ -69,7 +60,6 @@ struct sc_recorder_callbacks {
 bool
 sc_recorder_init(struct sc_recorder *recorder, const char *filename,
                  enum sc_record_format format, bool audio,
-                 struct sc_size declared_frame_size,
                  const struct sc_recorder_callbacks *cbs, void *cbs_userdata);
 
 bool

app/src/scrcpy.c

@@ -16,6 +16,7 @@
 #include "audio_player.h"
 #include "controller.h"
 #include "decoder.h"
+#include "delay_buffer.h"
 #include "demuxer.h"
 #include "events.h"
 #include "file_pusher.h"
@@ -47,8 +48,10 @@ struct scrcpy {
     struct sc_decoder video_decoder;
     struct sc_decoder audio_decoder;
     struct sc_recorder recorder;
+    struct sc_delay_buffer display_buffer;
 #ifdef HAVE_V4L2
     struct sc_v4l2_sink v4l2_sink;
+    struct sc_delay_buffer v4l2_buffer;
 #endif
     struct sc_controller controller;
     struct sc_file_pusher file_pusher;
@@ -172,7 +175,9 @@ event_loop(struct scrcpy *s) {
                 LOGD("User requested to quit");
                 return SCRCPY_EXIT_SUCCESS;
             default:
-                sc_screen_handle_event(&s->screen, &event);
+                if (!sc_screen_handle_event(&s->screen, &event)) {
+                    return SCRCPY_EXIT_FAILURE;
+                }
                 break;
         }
     }
@@ -218,12 +223,15 @@ sc_recorder_on_ended(struct sc_recorder *recorder, bool success,
 }
 
 static void
-sc_video_demuxer_on_ended(struct sc_demuxer *demuxer, bool eos,
-                          void *userdata) {
+sc_video_demuxer_on_ended(struct sc_demuxer *demuxer,
+                          enum sc_demuxer_status status, void *userdata) {
     (void) demuxer;
     (void) userdata;
 
-    if (eos) {
+    // The device may not decide to disable the video
+    assert(status != SC_DEMUXER_STATUS_DISABLED);
+
+    if (status == SC_DEMUXER_STATUS_EOS) {
         PUSH_EVENT(SC_EVENT_DEVICE_DISCONNECTED);
     } else {
         PUSH_EVENT(SC_EVENT_DEMUXER_ERROR);
@@ -231,20 +239,17 @@ sc_video_demuxer_on_ended(struct sc_demuxer *demuxer, bool eos,
 }
 
 static void
-sc_audio_demuxer_on_ended(struct sc_demuxer *demuxer, bool eos,
-                          void *userdata) {
+sc_audio_demuxer_on_ended(struct sc_demuxer *demuxer,
+                          enum sc_demuxer_status status, void *userdata) {
     (void) demuxer;
-    (void) userdata;
 
-    // Contrary to the video demuxer, keep mirroring if only the audio fails.
-    // 'eos' is true on end-of-stream, including when audio capture is not
-    // possible on the device (so that scrcpy continue to mirror video without
-    // failing).
-    // However, if an audio configuration failure occurs (for example the user
-    // explicitly selected an unknown audio encoder), 'eos' is false and scrcpy
-    // must exit.
+    const struct scrcpy_options *options = userdata;
 
-    if (!eos) {
+    // Contrary to the video demuxer, keep mirroring if only the audio fails
+    // (unless --require-audio is set).
+    if (status == SC_DEMUXER_STATUS_ERROR
+            || (status == SC_DEMUXER_STATUS_DISABLED
+                && options->require_audio)) {
         PUSH_EVENT(SC_EVENT_DEMUXER_ERROR);
     }
 }
@@ -443,7 +448,7 @@ scrcpy(struct scrcpy_options *options) {
             .on_ended = sc_audio_demuxer_on_ended,
         };
         sc_demuxer_init(&s->audio_demuxer, "audio", s->server.audio_socket,
-                        &audio_demuxer_cbs, NULL);
+                        &audio_demuxer_cbs, options);
     }
 
     bool needs_video_decoder = options->display;
@@ -453,11 +458,13 @@ scrcpy(struct scrcpy_options *options) {
 #endif
     if (needs_video_decoder) {
         sc_decoder_init(&s->video_decoder, "video");
-        sc_demuxer_add_sink(&s->video_demuxer, &s->video_decoder.packet_sink);
+        sc_packet_source_add_sink(&s->video_demuxer.packet_source,
+                                  &s->video_decoder.packet_sink);
     }
     if (needs_audio_decoder) {
         sc_decoder_init(&s->audio_decoder, "audio");
-        sc_demuxer_add_sink(&s->audio_demuxer, &s->audio_decoder.packet_sink);
+        sc_packet_source_add_sink(&s->audio_demuxer.packet_source,
+                                  &s->audio_decoder.packet_sink);
     }
 
     if (options->record_filename) {
@@ -466,7 +473,7 @@ scrcpy(struct scrcpy_options *options) {
         };
         if (!sc_recorder_init(&s->recorder, options->record_filename,
                               options->record_format, options->audio,
-                              info->frame_size, &recorder_cbs, NULL)) {
+                              &recorder_cbs, NULL)) {
             goto end;
         }
         recorder_initialized = true;
@@ -476,10 +483,11 @@ scrcpy(struct scrcpy_options *options) {
         }
         recorder_started = true;
 
-        sc_demuxer_add_sink(&s->video_demuxer, &s->recorder.video_packet_sink);
+        sc_packet_source_add_sink(&s->video_demuxer.packet_source,
+                                  &s->recorder.video_packet_sink);
         if (options->audio) {
-            sc_demuxer_add_sink(&s->audio_demuxer,
-                                &s->recorder.audio_packet_sink);
+            sc_packet_source_add_sink(&s->audio_demuxer.packet_source,
+                                      &s->recorder.audio_packet_sink);
         }
     }
 
@@ -652,7 +660,6 @@ aoa_hid_end:
             .clipboard_autosync = options->clipboard_autosync,
             .shortcut_mods = &options->shortcut_mods,
             .window_title = window_title,
-            .frame_size = info->frame_size,
             .always_on_top = options->always_on_top,
             .window_x = options->window_x,
             .window_y = options->window_y,
@@ -663,7 +670,6 @@ aoa_hid_end:
             .mipmaps = options->mipmaps,
             .fullscreen = options->fullscreen,
             .start_fps_counter = options->start_fps_counter,
-            .buffering_time = options->display_buffer,
         };
 
         if (!sc_screen_init(&s->screen, &screen_params)) {
@@ -671,22 +677,38 @@ aoa_hid_end:
         }
         screen_initialized = true;
 
-        sc_decoder_add_sink(&s->video_decoder, &s->screen.frame_sink);
+        struct sc_frame_source *src = &s->video_decoder.frame_source;
+        if (options->display_buffer) {
+            sc_delay_buffer_init(&s->display_buffer, options->display_buffer,
+                                 true);
+            sc_frame_source_add_sink(src, &s->display_buffer.frame_sink);
+            src = &s->display_buffer.frame_source;
+        }
+
+        sc_frame_source_add_sink(src, &s->screen.frame_sink);
 
         if (options->audio) {
-            sc_audio_player_init(&s->audio_player);
-            sc_decoder_add_sink(&s->audio_decoder, &s->audio_player.frame_sink);
+            sc_audio_player_init(&s->audio_player, options->audio_buffer,
+                                 options->audio_output_buffer);
+            sc_frame_source_add_sink(&s->audio_decoder.frame_source,
+                                     &s->audio_player.frame_sink);
         }
     }
 
 #ifdef HAVE_V4L2
     if (options->v4l2_device) {
-        if (!sc_v4l2_sink_init(&s->v4l2_sink, options->v4l2_device,
-                               info->frame_size, options->v4l2_buffer)) {
+        if (!sc_v4l2_sink_init(&s->v4l2_sink, options->v4l2_device)) {
             goto end;
         }
 
-        sc_decoder_add_sink(&s->video_decoder, &s->v4l2_sink.frame_sink);
+        struct sc_frame_source *src = &s->video_decoder.frame_source;
+        if (options->v4l2_buffer) {
+            sc_delay_buffer_init(&s->v4l2_buffer, options->v4l2_buffer, true);
+            sc_frame_source_add_sink(src, &s->v4l2_buffer.frame_sink);
+            src = &s->v4l2_buffer.frame_source;
+        }
+
+        sc_frame_source_add_sink(src, &s->v4l2_sink.frame_sink);
 
         v4l2_sink_initialized = true;
     }

app/src/screen.c

@@ -7,7 +7,6 @@
 #include "events.h"
 #include "icon.h"
 #include "options.h"
-#include "video_buffer.h"
 #include "util/log.h"
 
 #define DISPLAY_MARGINS 96
@@ -240,7 +239,7 @@ sc_screen_update_content_rect(struct sc_screen *screen) {
     }
 }
 
-static inline SDL_Texture *
+static bool
 create_texture(struct sc_screen *screen) {
     SDL_Renderer *renderer = screen->renderer;
     struct sc_size size = screen->frame_size;
@@ -248,7 +247,8 @@ create_texture(struct sc_screen *screen) {
                                              SDL_TEXTUREACCESS_STREAMING,
                                              size.width, size.height);
     if (!texture) {
-        return NULL;
+        LOGE("Could not create texture: %s", SDL_GetError());
+        return false;
     }
 
     if (screen->mipmaps) {
@@ -264,7 +264,8 @@ create_texture(struct sc_screen *screen) {
         SDL_GL_UnbindTexture(texture);
     }
 
-    return texture;
+    screen->texture = texture;
+    return true;
 }
 
 // render the texture to the renderer
@@ -336,7 +337,25 @@ sc_screen_frame_sink_open(struct sc_frame_sink *sink,
     (void) ctx;
 
     struct sc_screen *screen = DOWNCAST(sink);
-    (void) screen;
+
+    assert(ctx->width > 0 && ctx->width <= 0xFFFF);
+    assert(ctx->height > 0 && ctx->height <= 0xFFFF);
+    // screen->frame_size is never used before the event is pushed, and the
+    // event acts as a memory barrier so it is safe without mutex
+    screen->frame_size.width = ctx->width;
+    screen->frame_size.height = ctx->height;
+
+    static SDL_Event event = {
+        .type = SC_EVENT_SCREEN_INIT_SIZE,
+    };
+
+    // Post the event on the UI thread (the texture must be created from there)
+    int ret = SDL_PushEvent(&event);
+    if (ret < 0) {
+        LOGW("Could not post init size event: %s", SDL_GetError());
+        return false;
+    }
+
 #ifndef NDEBUG
     screen->open = true;
 #endif
@@ -359,30 +378,18 @@ sc_screen_frame_sink_close(struct sc_frame_sink *sink) {
 static bool
 sc_screen_frame_sink_push(struct sc_frame_sink *sink, const AVFrame *frame) {
     struct sc_screen *screen = DOWNCAST(sink);
-    return sc_video_buffer_push(&screen->vb, frame);
-}
 
-static void
-sc_video_buffer_on_new_frame(struct sc_video_buffer *vb, bool previous_skipped,
-                             void *userdata) {
-    (void) vb;
-    struct sc_screen *screen = userdata;
+    bool previous_skipped;
+    bool ok = sc_frame_buffer_push(&screen->fb, frame, &previous_skipped);
+    if (!ok) {
+        return false;
+    }
 
-    // event_failed implies previous_skipped (the previous frame may not have
-    // been consumed if the event was not sent)
-    assert(!screen->event_failed || previous_skipped);
-
-    bool need_new_event;
     if (previous_skipped) {
         sc_fps_counter_add_skipped_frame(&screen->fps_counter);
         // The SC_EVENT_NEW_FRAME triggered for the previous frame will consume
-        // this new frame instead, unless the previous event failed
-        need_new_event = screen->event_failed;
+        // this new frame instead
     } else {
-        need_new_event = true;
-    }
-
-    if (need_new_event) {
         static SDL_Event new_frame_event = {
             .type = SC_EVENT_NEW_FRAME,
         };
@@ -391,11 +398,11 @@ sc_video_buffer_on_new_frame(struct sc_video_buffer *vb, bool previous_skipped,
         int ret = SDL_PushEvent(&new_frame_event);
         if (ret < 0) {
             LOGW("Could not post new frame event: %s", SDL_GetError());
-            screen->event_failed = true;
-        } else {
-            screen->event_failed = false;
+            return false;
         }
     }
+
+    return true;
 }
 
 bool
@@ -405,7 +412,6 @@ sc_screen_init(struct sc_screen *screen,
     screen->has_frame = false;
     screen->fullscreen = false;
     screen->maximized = false;
-    screen->event_failed = false;
     screen->mouse_capture_key_pressed = 0;
 
     screen->req.x = params->window_x;
@@ -415,33 +421,19 @@ sc_screen_init(struct sc_screen *screen,
     screen->req.fullscreen = params->fullscreen;
     screen->req.start_fps_counter = params->start_fps_counter;
 
-    static const struct sc_video_buffer_callbacks cbs = {
-        .on_new_frame = sc_video_buffer_on_new_frame,
-    };
-
-    bool ok = sc_video_buffer_init(&screen->vb, params->buffering_time, &cbs,
-                                   screen);
+    bool ok = sc_frame_buffer_init(&screen->fb);
     if (!ok) {
         return false;
     }
 
-    ok = sc_video_buffer_start(&screen->vb);
-    if (!ok) {
-        goto error_destroy_video_buffer;
-    }
-
     if (!sc_fps_counter_init(&screen->fps_counter)) {
-        goto error_stop_and_join_video_buffer;
+        goto error_destroy_frame_buffer;
     }
 
-    screen->frame_size = params->frame_size;
     screen->rotation = params->rotation;
     if (screen->rotation) {
         LOGI("Initial display rotation set to %u", screen->rotation);
     }
-    struct sc_size content_size =
-        get_rotated_size(screen->frame_size, screen->rotation);
-    screen->content_size = content_size;
 
     uint32_t window_flags = SDL_WINDOW_HIDDEN
                           | SDL_WINDOW_RESIZABLE
@@ -509,18 +501,10 @@ sc_screen_init(struct sc_screen *screen,
         LOGW("Could not load icon");
     }
 
-    LOGI("Initial texture: %" PRIu16 "x%" PRIu16, params->frame_size.width,
-                                                  params->frame_size.height);
-    screen->texture = create_texture(screen);
-    if (!screen->texture) {
-        LOGE("Could not create texture: %s", SDL_GetError());
-        goto error_destroy_renderer;
-    }
-
     screen->frame = av_frame_alloc();
     if (!screen->frame) {
         LOG_OOM();
-        goto error_destroy_texture;
+        goto error_destroy_renderer;
     }
 
     struct sc_input_manager_params im_params = {
@@ -555,19 +539,14 @@ sc_screen_init(struct sc_screen *screen,
 
     return true;
 
-error_destroy_texture:
-    SDL_DestroyTexture(screen->texture);
 error_destroy_renderer:
     SDL_DestroyRenderer(screen->renderer);
 error_destroy_window:
     SDL_DestroyWindow(screen->window);
 error_destroy_fps_counter:
     sc_fps_counter_destroy(&screen->fps_counter);
-error_stop_and_join_video_buffer:
-    sc_video_buffer_stop(&screen->vb);
-    sc_video_buffer_join(&screen->vb);
-error_destroy_video_buffer:
-    sc_video_buffer_destroy(&screen->vb);
+error_destroy_frame_buffer:
+    sc_frame_buffer_destroy(&screen->fb);
 
     return false;
 }
@@ -604,13 +583,11 @@ sc_screen_hide_window(struct sc_screen *screen) {
 
 void
 sc_screen_interrupt(struct sc_screen *screen) {
-    sc_video_buffer_stop(&screen->vb);
     sc_fps_counter_interrupt(&screen->fps_counter);
 }
 
 void
 sc_screen_join(struct sc_screen *screen) {
-    sc_video_buffer_join(&screen->vb);
     sc_fps_counter_join(&screen->fps_counter);
 }
 
@@ -620,11 +597,13 @@ sc_screen_destroy(struct sc_screen *screen) {
     assert(!screen->open);
 #endif
     av_frame_free(&screen->frame);
-    SDL_DestroyTexture(screen->texture);
+    if (screen->texture) {
+        SDL_DestroyTexture(screen->texture);
+    }
     SDL_DestroyRenderer(screen->renderer);
     SDL_DestroyWindow(screen->window);
     sc_fps_counter_destroy(&screen->fps_counter);
-    sc_video_buffer_destroy(&screen->vb);
+    sc_frame_buffer_destroy(&screen->fb);
 }
 
 static void
@@ -684,6 +663,23 @@ sc_screen_set_rotation(struct sc_screen *screen, unsigned rotation) {
     sc_screen_render(screen, true);
 }
 
+static bool
+sc_screen_init_size(struct sc_screen *screen) {
+    // Before first frame
+    assert(!screen->has_frame);
+    assert(!screen->texture);
+
+    // The requested size is passed via screen->frame_size
+
+    struct sc_size content_size =
+        get_rotated_size(screen->frame_size, screen->rotation);
+    screen->content_size = content_size;
+
+    LOGI("Initial texture: %" PRIu16 "x%" PRIu16,
+                 screen->frame_size.width, screen->frame_size.height);
+    return create_texture(screen);
+}
+
 // recreate the texture and resize the window if the frame size has changed
 static bool
 prepare_for_frame(struct sc_screen *screen, struct sc_size new_frame_size) {
@@ -702,11 +698,7 @@ prepare_for_frame(struct sc_screen *screen, struct sc_size new_frame_size) {
 
         LOGI("New texture: %" PRIu16 "x%" PRIu16,
                      screen->frame_size.width, screen->frame_size.height);
-        screen->texture = create_texture(screen);
-        if (!screen->texture) {
-            LOGE("Could not create texture: %s", SDL_GetError());
-            return false;
-        }
+        return create_texture(screen);
     }
 
     return true;
@@ -730,7 +722,7 @@ update_texture(struct sc_screen *screen, const AVFrame *frame) {
 static bool
 sc_screen_update_frame(struct sc_screen *screen) {
     av_frame_unref(screen->frame);
-    sc_video_buffer_consume(&screen->vb, screen->frame);
+    sc_frame_buffer_consume(&screen->fb, screen->frame);
     AVFrame *frame = screen->frame;
 
     sc_fps_counter_add_rendered_frame(&screen->fps_counter);
@@ -819,22 +811,32 @@ sc_screen_is_mouse_capture_key(SDL_Keycode key) {
     return key == SDLK_LALT || key == SDLK_LGUI || key == SDLK_RGUI;
 }
 
-void
+bool
 sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event) {
     bool relative_mode = sc_screen_is_relative_mode(screen);
 
     switch (event->type) {
+        case SC_EVENT_SCREEN_INIT_SIZE: {
+            // The initial size is passed via screen->frame_size
+            bool ok = sc_screen_init_size(screen);
+            if (!ok) {
+                LOGE("Could not initialize screen size");
+                return false;
+            }
+            return true;
+        }
         case SC_EVENT_NEW_FRAME: {
             bool ok = sc_screen_update_frame(screen);
             if (!ok) {
-                LOGW("Frame update failed\n");
+                LOGE("Frame update failed\n");
+                return false;
             }
-            return;
+            return true;
         }
         case SDL_WINDOWEVENT:
             if (!screen->has_frame) {
                 // Do nothing
-                return;
+                return true;
             }
             switch (event->window.event) {
                 case SDL_WINDOWEVENT_EXPOSED:
@@ -865,7 +867,7 @@ sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event) {
                     }
                     break;
             }
-            return;
+            return true;
         case SDL_KEYDOWN:
             if (relative_mode) {
                 SDL_Keycode key = event->key.keysym.sym;
@@ -878,7 +880,7 @@ sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event) {
                         screen->mouse_capture_key_pressed = 0;
                     }
                     // Mouse capture keys are never forwarded to the device
-                    return;
+                    return true;
                 }
             }
             break;
@@ -894,7 +896,7 @@ sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event) {
                         sc_screen_toggle_mouse_capture(screen);
                     }
                     // Mouse capture keys are never forwarded to the device
-                    return;
+                    return true;
                 }
             }
             break;
@@ -904,7 +906,7 @@ sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event) {
             if (relative_mode && !sc_screen_get_mouse_capture(screen)) {
                 // Do not forward to input manager, the mouse will be captured
                 // on SDL_MOUSEBUTTONUP
-                return;
+                return true;
             }
             break;
         case SDL_FINGERMOTION:
@@ -913,18 +915,19 @@ sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event) {
             if (relative_mode) {
                 // Touch events are not compatible with relative mode
                 // (coordinates are not relative)
-                return;
+                return true;
             }
             break;
         case SDL_MOUSEBUTTONUP:
             if (relative_mode && !sc_screen_get_mouse_capture(screen)) {
                 sc_screen_set_mouse_capture(screen, true);
-                return;
+                return true;
             }
             break;
     }
 
     sc_input_manager_handle_event(&screen->im, event);
+    return true;
 }
 
 struct sc_point

app/src/screen.h

@@ -10,12 +10,12 @@
 #include "controller.h"
 #include "coords.h"
 #include "fps_counter.h"
+#include "frame_buffer.h"
 #include "input_manager.h"
 #include "opengl.h"
 #include "trait/key_processor.h"
 #include "trait/frame_sink.h"
 #include "trait/mouse_processor.h"
-#include "video_buffer.h"
 
 struct sc_screen {
     struct sc_frame_sink frame_sink; // frame sink trait
@@ -25,7 +25,7 @@ struct sc_screen {
 #endif
 
     struct sc_input_manager im;
-    struct sc_video_buffer vb;
+    struct sc_frame_buffer fb;
     struct sc_fps_counter fps_counter;
 
     // The initial requested window properties
@@ -59,8 +59,6 @@ struct sc_screen {
     bool maximized;
     bool mipmaps;
 
-    bool event_failed; // in case SDL_PushEvent() returned an error
-
     // To enable/disable mouse capture, a mouse capture key (LALT, LGUI or
     // RGUI) must be pressed. This variable tracks the pressed capture key.
     SDL_Keycode mouse_capture_key_pressed;
@@ -80,7 +78,6 @@ struct sc_screen_params {
     const struct sc_shortcut_mods *shortcut_mods;
 
     const char *window_title;
-    struct sc_size frame_size;
     bool always_on_top;
 
     int16_t window_x; // accepts SC_WINDOW_POSITION_UNDEFINED
@@ -95,8 +92,6 @@ struct sc_screen_params {
 
     bool fullscreen;
     bool start_fps_counter;
-
-    sc_tick buffering_time;
 };
 
 // initialize screen, create window, renderer and texture (window is hidden)
@@ -140,7 +135,8 @@ void
 sc_screen_set_rotation(struct sc_screen *screen, unsigned rotation);
 
 // react to SDL events
-void
+// If this function returns false, scrcpy must exit with an error.
+bool
 sc_screen_handle_event(struct sc_screen *screen, SDL_Event *event);
 
 // convert point from window coordinates to frame coordinates

app/src/server.c

@@ -173,6 +173,8 @@ sc_server_get_codec_name(enum sc_codec codec) {
             return "opus";
         case SC_CODEC_AAC:
             return "aac";
+        case SC_CODEC_RAW:
+            return "raw";
         default:
             return NULL;
     }
@@ -214,7 +216,7 @@ execute_server(struct sc_server *server,
 
     unsigned dyn_idx = count; // from there, the strings are allocated
 #define ADD_PARAM(fmt, ...) { \
-        char *p = (char *) &cmd[count]; \
+        char *p; \
         if (asprintf(&p, fmt, ## __VA_ARGS__) == -1) { \
             goto end; \
         } \
@@ -439,9 +441,9 @@ sc_server_init(struct sc_server *server, const struct sc_server_params *params,
 static bool
 device_read_info(struct sc_intr *intr, sc_socket device_socket,
                  struct sc_server_info *info) {
-    unsigned char buf[SC_DEVICE_NAME_FIELD_LENGTH + 4];
+    unsigned char buf[SC_DEVICE_NAME_FIELD_LENGTH];
     ssize_t r = net_recv_all_intr(intr, device_socket, buf, sizeof(buf));
-    if (r < SC_DEVICE_NAME_FIELD_LENGTH + 4) {
+    if (r < SC_DEVICE_NAME_FIELD_LENGTH) {
         LOGE("Could not retrieve device information");
         return false;
     }
@@ -449,9 +451,6 @@ device_read_info(struct sc_intr *intr, sc_socket device_socket,
     buf[SC_DEVICE_NAME_FIELD_LENGTH - 1] = '\0';
     memcpy(info->device_name, (char *) buf, sizeof(info->device_name));
 
-    unsigned char *fields = &buf[SC_DEVICE_NAME_FIELD_LENGTH];
-    info->frame_size.width = sc_read16be(fields);
-    info->frame_size.height = sc_read16be(&fields[2]);
     return true;
 }
 

app/src/server.h

@@ -18,7 +18,6 @@
 #define SC_DEVICE_NAME_FIELD_LENGTH 64
 struct sc_server_info {
     char device_name[SC_DEVICE_NAME_FIELD_LENGTH];
-    struct sc_size frame_size;
 };
 
 struct sc_server_params {

app/src/trait/frame_sink.h

@@ -7,8 +7,6 @@
 #include <stdbool.h>
 #include <libavcodec/avcodec.h>
 
-typedef struct AVFrame AVFrame;
-
 /**
  * Frame sink trait.
  *
@@ -19,6 +17,7 @@ struct sc_frame_sink {
 };
 
 struct sc_frame_sink_ops {
+    /* The codec context is valid until the sink is closed */
     bool (*open)(struct sc_frame_sink *sink, const AVCodecContext *ctx);
     void (*close)(struct sc_frame_sink *sink);
     bool (*push)(struct sc_frame_sink *sink, const AVFrame *frame);

app/src/trait/frame_source.c

@@ -0,0 +1,59 @@
+#include "frame_source.h"
+
+void
+sc_frame_source_init(struct sc_frame_source *source) {
+    source->sink_count = 0;
+}
+
+void
+sc_frame_source_add_sink(struct sc_frame_source *source,
+                         struct sc_frame_sink *sink) {
+    assert(source->sink_count < SC_FRAME_SOURCE_MAX_SINKS);
+    assert(sink);
+    assert(sink->ops);
+    source->sinks[source->sink_count++] = sink;
+}
+
+static void
+sc_frame_source_sinks_close_firsts(struct sc_frame_source *source,
+                                    unsigned count) {
+    while (count) {
+        struct sc_frame_sink *sink = source->sinks[--count];
+        sink->ops->close(sink);
+    }
+}
+
+bool
+sc_frame_source_sinks_open(struct sc_frame_source *source,
+                           const AVCodecContext *ctx) {
+    assert(source->sink_count);
+    for (unsigned i = 0; i < source->sink_count; ++i) {
+        struct sc_frame_sink *sink = source->sinks[i];
+        if (!sink->ops->open(sink, ctx)) {
+            sc_frame_source_sinks_close_firsts(source, i);
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void
+sc_frame_source_sinks_close(struct sc_frame_source *source) {
+    assert(source->sink_count);
+    sc_frame_source_sinks_close_firsts(source, source->sink_count);
+}
+
+bool
+sc_frame_source_sinks_push(struct sc_frame_source *source,
+                            const AVFrame *frame) {
+    assert(source->sink_count);
+    for (unsigned i = 0; i < source->sink_count; ++i) {
+        struct sc_frame_sink *sink = source->sinks[i];
+        if (!sink->ops->push(sink, frame)) {
+            return false;
+        }
+    }
+
+    return true;
+}

app/src/trait/frame_source.h

@@ -0,0 +1,38 @@
+#ifndef SC_FRAME_SOURCE_H
+#define SC_FRAME_SOURCE_H
+
+#include "common.h"
+
+#include "frame_sink.h"
+
+#define SC_FRAME_SOURCE_MAX_SINKS 2
+
+/**
+ * Frame source trait
+ *
+ * Component able to send AVFrames should implement this trait.
+ */
+struct sc_frame_source {
+    struct sc_frame_sink *sinks[SC_FRAME_SOURCE_MAX_SINKS];
+    unsigned sink_count;
+};
+
+void
+sc_frame_source_init(struct sc_frame_source *source);
+
+void
+sc_frame_source_add_sink(struct sc_frame_source *source,
+                         struct sc_frame_sink *sink);
+
+bool
+sc_frame_source_sinks_open(struct sc_frame_source *source,
+                           const AVCodecContext *ctx);
+
+void
+sc_frame_source_sinks_close(struct sc_frame_source *source);
+
+bool
+sc_frame_source_sinks_push(struct sc_frame_source *source,
+                           const AVFrame *frame);
+
+#endif

app/src/trait/packet_sink.h

@@ -5,9 +5,7 @@
 
 #include <assert.h>
 #include <stdbool.h>
-
-typedef struct AVCodec AVCodec;
-typedef struct AVPacket AVPacket;
+#include <libavcodec/avcodec.h>
 
 /**
  * Packet sink trait.
@@ -19,8 +17,8 @@ struct sc_packet_sink {
 };
 
 struct sc_packet_sink_ops {
-    /* The codec instance is static, it is valid until the end of the program */
-    bool (*open)(struct sc_packet_sink *sink, const AVCodec *codec);
+    /* The codec context is valid until the sink is closed */
+    bool (*open)(struct sc_packet_sink *sink, AVCodecContext *ctx);
     void (*close)(struct sc_packet_sink *sink);
     bool (*push)(struct sc_packet_sink *sink, const AVPacket *packet);
 

app/src/trait/packet_source.c

@@ -0,0 +1,70 @@
+#include "packet_source.h"
+
+void
+sc_packet_source_init(struct sc_packet_source *source) {
+    source->sink_count = 0;
+}
+
+void
+sc_packet_source_add_sink(struct sc_packet_source *source,
+                          struct sc_packet_sink *sink) {
+    assert(source->sink_count < SC_PACKET_SOURCE_MAX_SINKS);
+    assert(sink);
+    assert(sink->ops);
+    source->sinks[source->sink_count++] = sink;
+}
+
+static void
+sc_packet_source_sinks_close_firsts(struct sc_packet_source *source,
+                                    unsigned count) {
+    while (count) {
+        struct sc_packet_sink *sink = source->sinks[--count];
+        sink->ops->close(sink);
+    }
+}
+
+bool
+sc_packet_source_sinks_open(struct sc_packet_source *source,
+                            AVCodecContext *ctx) {
+    assert(source->sink_count);
+    for (unsigned i = 0; i < source->sink_count; ++i) {
+        struct sc_packet_sink *sink = source->sinks[i];
+        if (!sink->ops->open(sink, ctx)) {
+            sc_packet_source_sinks_close_firsts(source, i);
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void
+sc_packet_source_sinks_close(struct sc_packet_source *source) {
+    assert(source->sink_count);
+    sc_packet_source_sinks_close_firsts(source, source->sink_count);
+}
+
+bool
+sc_packet_source_sinks_push(struct sc_packet_source *source,
+                            const AVPacket *packet) {
+    assert(source->sink_count);
+    for (unsigned i = 0; i < source->sink_count; ++i) {
+        struct sc_packet_sink *sink = source->sinks[i];
+        if (!sink->ops->push(sink, packet)) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void
+sc_packet_source_sinks_disable(struct sc_packet_source *source) {
+    assert(source->sink_count);
+    for (unsigned i = 0; i < source->sink_count; ++i) {
+        struct sc_packet_sink *sink = source->sinks[i];
+        if (sink->ops->disable) {
+            sink->ops->disable(sink);
+        }
+    }
+}

app/src/trait/packet_source.h

@@ -0,0 +1,41 @@
+#ifndef SC_PACKET_SOURCE_H
+#define SC_PACKET_SOURCE_H
+
+#include "common.h"
+
+#include "packet_sink.h"
+
+#define SC_PACKET_SOURCE_MAX_SINKS 2
+
+/**
+ * Packet source trait
+ *
+ * Component able to send AVPackets should implement this trait.
+ */
+struct sc_packet_source {
+    struct sc_packet_sink *sinks[SC_PACKET_SOURCE_MAX_SINKS];
+    unsigned sink_count;
+};
+
+void
+sc_packet_source_init(struct sc_packet_source *source);
+
+void
+sc_packet_source_add_sink(struct sc_packet_source *source,
+                          struct sc_packet_sink *sink);
+
+bool
+sc_packet_source_sinks_open(struct sc_packet_source *source,
+                            AVCodecContext *ctx);
+
+void
+sc_packet_source_sinks_close(struct sc_packet_source *source);
+
+bool
+sc_packet_source_sinks_push(struct sc_packet_source *source,
+                            const AVPacket *packet);
+
+void
+sc_packet_source_sinks_disable(struct sc_packet_source *source);
+
+#endif

app/src/usb/aoa_hid.c

@@ -14,6 +14,8 @@
 
 #define DEFAULT_TIMEOUT 1000
 
+#define SC_HID_EVENT_QUEUE_MAX 64
+
 static void
 sc_hid_event_log(const struct sc_hid_event *event) {
     // HID Event: [00] FF FF FF FF...
@@ -48,14 +50,20 @@ sc_hid_event_destroy(struct sc_hid_event *hid_event) {
 bool
 sc_aoa_init(struct sc_aoa *aoa, struct sc_usb *usb,
             struct sc_acksync *acksync) {
-    cbuf_init(&aoa->queue);
+    sc_vecdeque_init(&aoa->queue);
+
+    if (!sc_vecdeque_reserve(&aoa->queue, SC_HID_EVENT_QUEUE_MAX)) {
+        return false;
+    }
 
     if (!sc_mutex_init(&aoa->mutex)) {
+        sc_vecdeque_destroy(&aoa->queue);
         return false;
     }
 
     if (!sc_cond_init(&aoa->event_cond)) {
         sc_mutex_destroy(&aoa->mutex);
+        sc_vecdeque_destroy(&aoa->queue);
         return false;
     }
 
@@ -69,9 +77,10 @@ sc_aoa_init(struct sc_aoa *aoa, struct sc_usb *usb,
 void
 sc_aoa_destroy(struct sc_aoa *aoa) {
     // Destroy remaining events
-    struct sc_hid_event event;
-    while (cbuf_take(&aoa->queue, &event)) {
-        sc_hid_event_destroy(&event);
+    while (!sc_vecdeque_is_empty(&aoa->queue)) {
+        struct sc_hid_event *event = sc_vecdeque_popref(&aoa->queue);
+        assert(event);
+        sc_hid_event_destroy(event);
     }
 
     sc_cond_destroy(&aoa->event_cond);
@@ -212,13 +221,19 @@ sc_aoa_push_hid_event(struct sc_aoa *aoa, const struct sc_hid_event *event) {
     }
 
     sc_mutex_lock(&aoa->mutex);
-    bool was_empty = cbuf_is_empty(&aoa->queue);
-    bool res = cbuf_push(&aoa->queue, *event);
-    if (was_empty) {
-        sc_cond_signal(&aoa->event_cond);
+    bool full = sc_vecdeque_is_full(&aoa->queue);
+    if (!full) {
+        bool was_empty = sc_vecdeque_is_empty(&aoa->queue);
+        sc_vecdeque_push_noresize(&aoa->queue, *event);
+        if (was_empty) {
+            sc_cond_signal(&aoa->event_cond);
+        }
     }
+    // Otherwise (if the queue is full), the event is discarded
+
     sc_mutex_unlock(&aoa->mutex);
-    return res;
+
+    return !full;
 }
 
 static int
@@ -227,7 +242,7 @@ run_aoa_thread(void *data) {
 
     for (;;) {
         sc_mutex_lock(&aoa->mutex);
-        while (!aoa->stopped && cbuf_is_empty(&aoa->queue)) {
+        while (!aoa->stopped && sc_vecdeque_is_empty(&aoa->queue)) {
             sc_cond_wait(&aoa->event_cond, &aoa->mutex);
         }
         if (aoa->stopped) {
@@ -235,11 +250,9 @@ run_aoa_thread(void *data) {
             sc_mutex_unlock(&aoa->mutex);
             break;
         }
-        struct sc_hid_event event;
-        bool non_empty = cbuf_take(&aoa->queue, &event);
-        assert(non_empty);
-        (void) non_empty;
 
+        assert(!sc_vecdeque_is_empty(&aoa->queue));
+        struct sc_hid_event event = sc_vecdeque_pop(&aoa->queue);
         uint64_t ack_to_wait = event.ack_to_wait;
         sc_mutex_unlock(&aoa->mutex);
 

app/src/usb/aoa_hid.h

@@ -8,9 +8,9 @@
 
 #include "usb.h"
 #include "util/acksync.h"
-#include "util/cbuf.h"
 #include "util/thread.h"
 #include "util/tick.h"
+#include "util/vecdeque.h"
 
 struct sc_hid_event {
     uint16_t accessory_id;
@@ -27,7 +27,7 @@ sc_hid_event_init(struct sc_hid_event *hid_event, uint16_t accessory_id,
 void
 sc_hid_event_destroy(struct sc_hid_event *hid_event);
 
-struct sc_hid_event_queue CBUF(struct sc_hid_event, 64);
+struct sc_hid_event_queue SC_VECDEQUE(struct sc_hid_event);
 
 struct sc_aoa {
     struct sc_usb *usb;

app/src/util/audiobuf.h

@@ -0,0 +1,94 @@
+#ifndef SC_AUDIOBUF_H
+#define SC_AUDIOBUF_H
+
+#include "common.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "util/bytebuf.h"
+
+/**
+ * Wrapper around bytebuf to read and write samples
+ *
+ * Each sample takes sample_size bytes.
+ */
+struct sc_audiobuf {
+    struct sc_bytebuf buf;
+    size_t sample_size;
+};
+
+static inline uint32_t
+sc_audiobuf_to_samples(struct sc_audiobuf *buf, size_t bytes) {
+    assert(bytes % buf->sample_size == 0);
+    return bytes / buf->sample_size;
+}
+
+static inline size_t
+sc_audiobuf_to_bytes(struct sc_audiobuf *buf, uint32_t samples) {
+    return samples * buf->sample_size;
+}
+
+static inline bool
+sc_audiobuf_init(struct sc_audiobuf *buf, size_t sample_size,
+                 uint32_t capacity) {
+    buf->sample_size = sample_size;
+    return sc_bytebuf_init(&buf->buf, capacity * sample_size + 1);
+}
+
+static inline void
+sc_audiobuf_read(struct sc_audiobuf *buf, uint8_t *to, uint32_t samples) {
+    size_t bytes = sc_audiobuf_to_bytes(buf, samples);
+    sc_bytebuf_read(&buf->buf, to, bytes);
+}
+
+static inline void
+sc_audiobuf_skip(struct sc_audiobuf *buf, uint32_t samples) {
+    size_t bytes = sc_audiobuf_to_bytes(buf, samples);
+    sc_bytebuf_skip(&buf->buf, bytes);
+}
+
+static inline void
+sc_audiobuf_write(struct sc_audiobuf *buf, const uint8_t *from,
+                  uint32_t samples) {
+    size_t bytes = sc_audiobuf_to_bytes(buf, samples);
+    sc_bytebuf_write(&buf->buf, from, bytes);
+}
+
+static inline void
+sc_audiobuf_prepare_write(struct sc_audiobuf *buf, const uint8_t *from,
+                          uint32_t samples) {
+    size_t bytes = sc_audiobuf_to_bytes(buf, samples);
+    sc_bytebuf_prepare_write(&buf->buf, from, bytes);
+}
+
+static inline void
+sc_audiobuf_commit_write(struct sc_audiobuf *buf, uint32_t samples) {
+    size_t bytes = sc_audiobuf_to_bytes(buf, samples);
+    sc_bytebuf_commit_write(&buf->buf, bytes);
+}
+
+static inline uint32_t
+sc_audiobuf_can_read(struct sc_audiobuf *buf) {
+    size_t bytes = sc_bytebuf_can_read(&buf->buf);
+    return sc_audiobuf_to_samples(buf, bytes);
+}
+
+static inline uint32_t
+sc_audiobuf_can_write(struct sc_audiobuf *buf) {
+    size_t bytes = sc_bytebuf_can_write(&buf->buf);
+    return sc_audiobuf_to_samples(buf, bytes);
+}
+
+static inline uint32_t
+sc_audiobuf_capacity(struct sc_audiobuf *buf) {
+    size_t bytes = sc_bytebuf_capacity(&buf->buf);
+    return sc_audiobuf_to_samples(buf, bytes);
+}
+
+static inline void
+sc_audiobuf_destroy(struct sc_audiobuf *buf) {
+    sc_bytebuf_destroy(&buf->buf);
+}
+
+#endif

app/src/util/average.c

@@ -19,8 +19,8 @@ sc_average_push(struct sc_average *avg, float value) {
     avg->avg = ((avg->count - 1) * avg->avg + value) / avg->count;
 }
 
-bool
-sc_average_get(struct sc_average *avg, float *value) {
-    *value = avg->avg;
-    return avg->count;
+float
+sc_average_get(struct sc_average *avg) {
+    assert(avg->count);
+    return avg->avg;
 }

app/src/util/average.h

@@ -22,15 +22,19 @@ struct sc_average {
 void
 sc_average_init(struct sc_average *avg, unsigned range);
 
-/* Push a new value to update the "rolling" average */
+/**
+ * Push a new value to update the "rolling" average
+ */
 void
 sc_average_push(struct sc_average *avg, float value);
 
-/* Get the current average value (if available)
+/**
+ * Get the current average value
  *
- * An average is available if sc_average_push() has been called at least once.
+ * It is an error to call this function if sc_average_push() has not been
+ * called at least once.
  */
-bool
-sc_average_get(struct sc_average *avg, float *value);
+float
+sc_average_get(struct sc_average *avg);
 
 #endif

app/src/util/bytebuf.c

@@ -9,7 +9,6 @@
 bool
 sc_bytebuf_init(struct sc_bytebuf *buf, size_t alloc_size) {
     assert(alloc_size);
-    // sufficient, but use more for alignment.
     buf->data = malloc(alloc_size);
     if (!buf->data) {
         LOG_OOM();
@@ -31,7 +30,7 @@ sc_bytebuf_destroy(struct sc_bytebuf *buf) {
 void
 sc_bytebuf_read(struct sc_bytebuf *buf, uint8_t *to, size_t len) {
     assert(len);
-    assert(sc_bytebuf_read_remaining(buf) >= len);
+    assert(len <= sc_bytebuf_can_read(buf));
     assert(buf->tail != buf->head); // the buffer could not be empty
 
     size_t right_limit = buf->tail < buf->head ? buf->head : buf->alloc_size;
@@ -51,42 +50,40 @@ sc_bytebuf_read(struct sc_bytebuf *buf, uint8_t *to, size_t len) {
 void
 sc_bytebuf_skip(struct sc_bytebuf *buf, size_t len) {
     assert(len);
-    assert(sc_bytebuf_read_remaining(buf) >= len);
+    assert(len <= sc_bytebuf_can_read(buf));
     assert(buf->tail != buf->head); // the buffer could not be empty
 
     buf->tail = (buf->tail + len) % buf->alloc_size;
 }
 
-void
-sc_bytebuf_write(struct sc_bytebuf *buf, const uint8_t *from, size_t len) {
-    assert(len);
-
-    size_t max_len = buf->alloc_size - 1;
-    if (len >= max_len) {
-        // Copy only the right-most bytes
-        memcpy(buf->data, from + len - max_len, max_len);
-        buf->tail = 0;
-        buf->head = max_len;
-        return;
-    }
-
-    size_t right_limit = buf->head < buf->tail ? buf->tail : buf->alloc_size;
-    size_t right_len = right_limit - buf->head;
+static inline void
+sc_bytebuf_write_step0(struct sc_bytebuf *buf, const uint8_t *from,
+                       size_t len) {
+    size_t right_len = buf->alloc_size - buf->head;
     if (len < right_len) {
         right_len = len;
     }
     memcpy(buf->data + buf->head, from, right_len);
+
     if (len > right_len) {
         memcpy(buf->data, from + right_len, len - right_len);
     }
+}
 
-    size_t empty_space = sc_bytebuf_write_remaining(buf);
-    if (len > empty_space) {
-        buf->tail = (buf->tail + len - empty_space) % buf->alloc_size;
-    }
+static inline void
+sc_bytebuf_write_step1(struct sc_bytebuf *buf, size_t len) {
     buf->head = (buf->head + len) % buf->alloc_size;
 }
 
+void
+sc_bytebuf_write(struct sc_bytebuf *buf, const uint8_t *from, size_t len) {
+    assert(len);
+    assert(len <= sc_bytebuf_can_write(buf));
+
+    sc_bytebuf_write_step0(buf, from, len);
+    sc_bytebuf_write_step1(buf, len);
+}
+
 void
 sc_bytebuf_prepare_write(struct sc_bytebuf *buf, const uint8_t *from,
                          size_t len) {
@@ -97,20 +94,11 @@ sc_bytebuf_prepare_write(struct sc_bytebuf *buf, const uint8_t *from,
     // be called with lock held).
 
     assert(len < buf->alloc_size - 1);
-
-    size_t right_len = buf->alloc_size - buf->head;
-    if (len < right_len) {
-        right_len = len;
-    }
-
-    memcpy(buf->data + buf->head, from, right_len);
-    if (len > right_len) {
-        memcpy(buf->data, from + right_len, len - right_len);
-    }
+    sc_bytebuf_write_step0(buf, from, len);
 }
 
 void
 sc_bytebuf_commit_write(struct sc_bytebuf *buf, size_t len) {
-    assert(len <= sc_bytebuf_write_remaining(buf));
-    buf->head = (buf->head + len) % buf->alloc_size;
+    assert(len <= sc_bytebuf_can_write(buf));
+    sc_bytebuf_write_step1(buf, len);
 }

app/src/util/bytebuf.h

@@ -11,10 +11,10 @@ struct sc_bytebuf {
     // The actual capacity is (allocated - 1) so that head == tail is
     // non-ambiguous
     size_t alloc_size;
-    size_t head;
-    size_t tail;
+    size_t head; // writter cursor
+    size_t tail; // reader cursor
     // empty: tail == head
-    // full: (tail + 1) % allocated == head
+    // full: ((tail + 1) % alloc_size) == head
 };
 
 bool
@@ -23,10 +23,10 @@ sc_bytebuf_init(struct sc_bytebuf *buf, size_t alloc_size);
 /**
  * Copy from the bytebuf to a user-provided array
  *
- * The caller must check that len <= buf->len (it is an error to attempt to read
- * more bytes than available).
+ * The caller must check that len <= sc_bytebuf_read_available() (it is an
+ * error to attempt to read more bytes than available).
  *
- * This function is guaranteed to not change the head.
+ * This function is guaranteed not to write to buf->head.
  */
 void
 sc_bytebuf_read(struct sc_bytebuf *buf, uint8_t *to, size_t len);
@@ -34,13 +34,13 @@ sc_bytebuf_read(struct sc_bytebuf *buf, uint8_t *to, size_t len);
 /**
  * Drop len bytes from the buffer
  *
- * The caller must check that len <= buf->len (it is an error to attempt to skip
- * more bytes than available).
+ * The caller must check that len <= sc_bytebuf_read_available() (it is an
+ * error to attempt to skip more bytes than available).
  *
- * This function is guaranteed to not change the head.
+ * This function is guaranteed not to write to buf->head.
  *
  * It is equivalent to call sc_bytebuf_read() to some array and discard the
- * array (but more efficient since there is no copy).
+ * array (but this function is more efficient since there is no copy).
  */
 void
 sc_bytebuf_skip(struct sc_bytebuf *buf, size_t len);
@@ -48,9 +48,10 @@ sc_bytebuf_skip(struct sc_bytebuf *buf, size_t len);
 /**
  * Copy the user-provided array to the bytebuf
  *
- * The length of the input array is not restricted:
- * if len >= sc_bytebuf_write_remaining(buf), then the excessive input bytes
- * will overwrite the oldest bytes in the buffer.
+ * The caller must check that len <= sc_bytebuf_write_available() (it is an
+ * error to write more bytes than the remaining available space).
+ *
+ * This function is guaranteed not to write to buf->tail.
  */
 void
 sc_bytebuf_write(struct sc_bytebuf *buf, const uint8_t *from, size_t len);
@@ -58,14 +59,16 @@ sc_bytebuf_write(struct sc_bytebuf *buf, const uint8_t *from, size_t len);
 /**
  * Copy the user-provided array to the bytebuf, but do not advance the cursor
  *
- * The caller must check that len <= buf->len (it is an error to attempt to
- * write more bytes than available).
+ * The caller must check that len <= sc_bytebuf_write_available() (it is an
+ * error to write more bytes than the remaining available space).
  *
  * After this function is called, the write must be committed with
  * sc_bytebuf_commit_write().
  *
  * The purpose of this mechanism is to acquire a lock only to commit the write,
  * but not to perform the actual copy.
+ *
+ * This function is guaranteed not to access buf->tail.
  */
 void
 sc_bytebuf_prepare_write(struct sc_bytebuf *buf, const uint8_t *from,
@@ -83,21 +86,28 @@ sc_bytebuf_commit_write(struct sc_bytebuf *buf, size_t len);
  * It is an error to read more bytes than available.
  */
 static inline size_t
-sc_bytebuf_read_remaining(struct sc_bytebuf *buf) {
+sc_bytebuf_can_read(struct sc_bytebuf *buf) {
     return (buf->alloc_size + buf->head - buf->tail) % buf->alloc_size;
 }
 
 /**
- * Return the number of bytes which can be written without overwriting
+ * Return the number of bytes which can be written
  *
- * It is not an error to write more bytes than the available space, but this
- * would overwrite the oldest bytes in the buffer.
+ * It is an error to write more bytes than available.
  */
 static inline size_t
-sc_bytebuf_write_remaining(struct sc_bytebuf *buf) {
+sc_bytebuf_can_write(struct sc_bytebuf *buf) {
     return (buf->alloc_size + buf->tail - buf->head - 1) % buf->alloc_size;
 }
 
+/**
+ * Return the actual capacity of the buffer (can_read() + can_write())
+ */
+static inline size_t
+sc_bytebuf_capacity(struct sc_bytebuf *buf) {
+    return buf->alloc_size - 1;
+}
+
 void
 sc_bytebuf_destroy(struct sc_bytebuf *buf);
 

app/src/util/cbuf.h

@@ -1,52 +0,0 @@
-// generic circular buffer (bounded queue) implementation
-#ifndef SC_CBUF_H
-#define SC_CBUF_H
-
-#include "common.h"
-
-#include <stdbool.h>
-#include <unistd.h>
-
-// To define a circular buffer type of 20 ints:
-//     struct cbuf_int CBUF(int, 20);
-//
-// data has length CAP + 1 to distinguish empty vs full.
-#define CBUF(TYPE, CAP) { \
-    TYPE data[(CAP) + 1]; \
-    size_t head; \
-    size_t tail; \
-}
-
-#define cbuf_size_(PCBUF) \
-    (sizeof((PCBUF)->data) / sizeof(*(PCBUF)->data))
-
-#define cbuf_is_empty(PCBUF) \
-    ((PCBUF)->head == (PCBUF)->tail)
-
-#define cbuf_is_full(PCBUF) \
-    (((PCBUF)->head + 1) % cbuf_size_(PCBUF) == (PCBUF)->tail)
-
-#define cbuf_init(PCBUF) \
-    (void) ((PCBUF)->head = (PCBUF)->tail = 0)
-
-#define cbuf_push(PCBUF, ITEM) \
-    ({ \
-        bool ok = !cbuf_is_full(PCBUF); \
-        if (ok) { \
-            (PCBUF)->data[(PCBUF)->head] = (ITEM); \
-            (PCBUF)->head = ((PCBUF)->head + 1) % cbuf_size_(PCBUF); \
-        } \
-        ok; \
-    })
-
-#define cbuf_take(PCBUF, PITEM) \
-    ({ \
-        bool ok = !cbuf_is_empty(PCBUF); \
-        if (ok) { \
-            *(PITEM) = (PCBUF)->data[(PCBUF)->tail]; \
-            (PCBUF)->tail = ((PCBUF)->tail + 1) % cbuf_size_(PCBUF); \
-        } \
-        ok; \
-    })
-
-#endif

app/src/util/log.c

@@ -125,8 +125,30 @@ sc_av_log_callback(void *avcl, int level, const char *fmt, va_list vl) {
     free(local_fmt);
 }
 
+static const char *const sc_sdl_log_priority_names[SDL_NUM_LOG_PRIORITIES] = {
+    [SDL_LOG_PRIORITY_VERBOSE] = "VERBOSE",
+    [SDL_LOG_PRIORITY_DEBUG] = "DEBUG",
+    [SDL_LOG_PRIORITY_INFO] = "INFO",
+    [SDL_LOG_PRIORITY_WARN] = "WARN",
+    [SDL_LOG_PRIORITY_ERROR] = "ERROR",
+    [SDL_LOG_PRIORITY_CRITICAL] = "CRITICAL",
+};
+
+static void SDLCALL
+sc_sdl_log_print(void *userdata, int category, SDL_LogPriority priority,
+                 const char *message) {
+    (void) userdata;
+    (void) category;
+
+    FILE *out = priority < SDL_LOG_PRIORITY_WARN ? stdout : stderr;
+    assert(priority < SDL_NUM_LOG_PRIORITIES);
+    const char *prio_name = sc_sdl_log_priority_names[priority];
+    fprintf(out, "%s: %s\n", prio_name, message);
+}
+
 void
 sc_log_configure() {
+    SDL_LogSetOutputFunction(sc_sdl_log_print, NULL);
     // Redirect FFmpeg logs to SDL logs
     av_log_set_callback(sc_av_log_callback);
 }

app/src/util/memory.c

@@ -0,0 +1,14 @@
+#include "memory.h"
+
+#include <stdlib.h>
+#include <errno.h>
+
+void *
+sc_allocarray(size_t nmemb, size_t size) {
+    size_t bytes;
+    if (__builtin_mul_overflow(nmemb, size, &bytes)) {
+      errno = ENOMEM;
+      return NULL;
+    }
+    return malloc(bytes);
+}

app/src/util/memory.h

@@ -0,0 +1,15 @@
+#ifndef SC_MEMORY_H
+#define SC_MEMORY_H
+
+#include <stddef.h>
+
+/**
+ * Allocate an array of `nmemb` items of `size` bytes each
+ *
+ * Like calloc(), but without initialization.
+ * Like reallocarray(), but without reallocation.
+ */
+void *
+sc_allocarray(size_t nmemb, size_t size);
+
+#endif

app/src/util/queue.h

@@ -1,77 +0,0 @@
-// generic intrusive FIFO queue
-#ifndef SC_QUEUE_H
-#define SC_QUEUE_H
-
-#include "common.h"
-
-#include <assert.h>
-#include <stdbool.h>
-#include <stddef.h>
-
-// To define a queue type of "struct foo":
-//    struct queue_foo QUEUE(struct foo);
-#define SC_QUEUE(TYPE) { \
-    TYPE *first; \
-    TYPE *last; \
-}
-
-#define sc_queue_init(PQ) \
-    (void) ((PQ)->first = (PQ)->last = NULL)
-
-#define sc_queue_is_empty(PQ) \
-    !(PQ)->first
-
-// NEXTFIELD is the field in the ITEM type used for intrusive linked-list
-//
-// For example:
-//    struct foo {
-//        int value;
-//        struct foo *next;
-//    };
-//
-//    // define the type "struct my_queue"
-//    struct my_queue SC_QUEUE(struct foo);
-//
-//    struct my_queue queue;
-//    sc_queue_init(&queue);
-//
-//    struct foo v1 = { .value = 42 };
-//    struct foo v2 = { .value = 27 };
-//
-//    sc_queue_push(&queue, next, v1);
-//    sc_queue_push(&queue, next, v2);
-//
-//    struct foo *foo;
-//    sc_queue_take(&queue, next, &foo);
-//    assert(foo->value == 42);
-//    sc_queue_take(&queue, next, &foo);
-//    assert(foo->value == 27);
-//    assert(sc_queue_is_empty(&queue));
-//
-
-// push a new item into the queue
-#define sc_queue_push(PQ, NEXTFIELD, ITEM) \
-    (void) ({ \
-        (ITEM)->NEXTFIELD = NULL; \
-        if (sc_queue_is_empty(PQ)) { \
-            (PQ)->first = (PQ)->last = (ITEM); \
-        } else { \
-            (PQ)->last->NEXTFIELD = (ITEM); \
-            (PQ)->last = (ITEM); \
-        } \
-    })
-
-// take the next item and remove it from the queue (the queue must not be empty)
-// the result is stored in *(PITEM)
-// (without typeof(), we could not store a local variable having the correct
-// type so that we can "return" it)
-#define sc_queue_take(PQ, NEXTFIELD, PITEM) \
-    (void) ({ \
-        assert(!sc_queue_is_empty(PQ)); \
-        *(PITEM) = (PQ)->first; \
-        (PQ)->first = (PQ)->first->NEXTFIELD; \
-    })
-    // no need to update (PQ)->last if the queue is left empty:
-    // (PQ)->last is undefined if !(PQ)->first anyway
-
-#endif

app/src/util/thread.c

@@ -23,6 +23,39 @@ sc_thread_create(sc_thread *thread, sc_thread_fn fn, const char *name,
     return true;
 }
 
+static SDL_ThreadPriority
+to_sdl_thread_priority(enum sc_thread_priority priority) {
+    switch (priority) {
+        case SC_THREAD_PRIORITY_TIME_CRITICAL:
+#ifdef SCRCPY_SDL_HAS_THREAD_PRIORITY_TIME_CRITICAL
+            return SDL_THREAD_PRIORITY_TIME_CRITICAL;
+#else
+            // fall through
+#endif
+        case SC_THREAD_PRIORITY_HIGH:
+            return SDL_THREAD_PRIORITY_HIGH;
+        case SC_THREAD_PRIORITY_NORMAL:
+            return SDL_THREAD_PRIORITY_NORMAL;
+        case SC_THREAD_PRIORITY_LOW:
+            return SDL_THREAD_PRIORITY_LOW;
+        default:
+            assert(!"Unknown thread priority");
+            return 0;
+    }
+}
+
+bool
+sc_thread_set_priority(enum sc_thread_priority priority) {
+    SDL_ThreadPriority sdl_priority = to_sdl_thread_priority(priority);
+    int r = SDL_SetThreadPriority(sdl_priority);
+    if (r) {
+        LOGD("Could not set thread priority: %s", SDL_GetError());
+        return false;
+    }
+
+    return true;
+}
+
 void
 sc_thread_join(sc_thread *thread, int *status) {
     SDL_WaitThread(thread->thread, status);

app/src/util/thread.h

@@ -21,6 +21,13 @@ typedef struct sc_thread {
     SDL_Thread *thread;
 } sc_thread;
 
+enum sc_thread_priority {
+    SC_THREAD_PRIORITY_LOW,
+    SC_THREAD_PRIORITY_NORMAL,
+    SC_THREAD_PRIORITY_HIGH,
+    SC_THREAD_PRIORITY_TIME_CRITICAL,
+};
+
 typedef struct sc_mutex {
     SDL_mutex *mutex;
 #ifndef NDEBUG
@@ -39,6 +46,9 @@ sc_thread_create(sc_thread *thread, sc_thread_fn fn, const char *name,
 void
 sc_thread_join(sc_thread *thread, int *status);
 
+bool
+sc_thread_set_priority(enum sc_thread_priority priority);
+
 bool
 sc_mutex_init(sc_mutex *mutex);
 

app/src/util/vecdeque.h

@@ -0,0 +1,379 @@
+#ifndef SC_VECDEQUE_H
+#define SC_VECDEQUE_H
+
+#include "common.h"
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "util/memory.h"
+
+/**
+ * A double-ended queue implemented with a growable ring buffer.
+ *
+ * Inspired from the Rust VecDeque type:
+ * <https://doc.rust-lang.org/std/collections/struct.VecDeque.html>
+ */
+
+/**
+ * VecDeque struct body
+ *
+ * A VecDeque is a dynamic ring-buffer, managed by the sc_vecdeque_* helpers.
+ *
+ * It is generic over the type of its items, so it is implemented via macros.
+ *
+ * To use a VecDeque, a new type must be defined:
+ *
+ *     struct vecdeque_int SC_VECDEQUE(int);
+ *
+ * The struct may be anonymous:
+ *
+ *     struct SC_VECDEQUE(const char *) names;
+ *
+ * Functions and macros having name ending with '_' are private.
+ */
+#define SC_VECDEQUE(type) { \
+    size_t cap; \
+    size_t origin; \
+    size_t size; \
+    type *data; \
+}
+
+/**
+ * Static initializer for a VecDeque
+ */
+#define SC_VECDEQUE_INITIALIZER { 0, 0, 0, NULL }
+
+/**
+ * Initialize an empty VecDeque
+ */
+#define sc_vecdeque_init(pv) \
+({ \
+    (pv)->cap = 0; \
+    (pv)->origin = 0; \
+    (pv)->size = 0; \
+    (pv)->data = NULL; \
+})
+
+/**
+ * Destroy a VecDeque
+ */
+#define sc_vecdeque_destroy(pv) \
+    free((pv)->data)
+
+/**
+ * Clear a VecDeque
+ *
+ * Remove all items.
+ */
+#define sc_vecdeque_clear(pv) \
+(void) ({ \
+    sc_vecdeque_destroy(pv); \
+    sc_vecdeque_init(pv); \
+})
+
+/**
+ * Returns the content size
+ */
+#define sc_vecdeque_size(pv) \
+    (pv)->size
+
+/**
+ * Return whether the VecDeque is empty (i.e. its size is 0)
+ */
+#define sc_vecdeque_is_empty(pv) \
+    ((pv)->size == 0)
+
+/**
+ * Return whether the VecDeque is full
+ *
+ * A VecDeque is full when its size equals its current capacity. However, it
+ * does not prevent to push a new item (with sc_vecdeque_push()), since this
+ * will increase its capacity.
+ */
+#define sc_vecdeque_is_full(pv) \
+    ((pv)->size == (pv)->cap)
+
+/**
+ * The minimal allocation size, in number of items
+ *
+ * Private.
+ */
+#define SC_VECDEQUE_MINCAP_ ((size_t) 10)
+
+/**
+ * The maximal allocation size, in number of items
+ *
+ * Use SIZE_MAX/2 to fit in ssize_t, and so that cap*1.5 does not overflow.
+ *
+ * Private.
+ */
+#define sc_vecdeque_max_cap_(pv) (SIZE_MAX / 2 / sizeof(*(pv)->data))
+
+/**
+ * Realloc the internal array to a specific capacity
+ *
+ * On reallocation success, update the VecDeque capacity (`*pcap`) and origin
+ * (`*porigin`), and return the reallocated data.
+ *
+ * On reallocation failure, return NULL without any change.
+ *
+ * Private.
+ *
+ * \param ptr the current `data` field of the SC_VECDEQUE to realloc
+ * \param newcap the requested capacity, in number of items
+ * \param item_size the size of one item (the generic type is unknown from this
+ *                  function)
+ * \param pcap a pointer to the `cap` field of the SC_VECDEQUE [IN/OUT]
+ * \param porigin a pointer to pv->origin [IN/OUT]
+ * \param size the `size` field of the SC_VECDEQUE
+ * \return the new array to assign to the `data` field of the SC_VECDEQUE (if
+ *         not NULL)
+ */
+static inline void *
+sc_vecdeque_reallocdata_(void *ptr, size_t newcap, size_t item_size,
+                         size_t *pcap, size_t *porigin, size_t size) {
+
+    size_t oldcap = *pcap;
+    size_t oldorigin = *porigin;
+
+    assert(newcap > oldcap); // Could only grow
+
+    if (oldorigin + size <= oldcap) {
+        // The current content will stay in place, just realloc
+        //
+        // As an example, here is the content of a ring-buffer (oldcap=10)
+        // before the realloc:
+        //
+        //     _ _ 2 3 4 5 6 7 _ _
+        //         ^
+        //         origin
+        //
+        // It is resized (newcap=15), e.g. with sc_vecdeque_reserve():
+        //
+        //     _ _ 2 3 4 5 6 7 _ _ _ _ _ _ _
+        //         ^
+        //         origin
+
+        void *newptr = reallocarray(ptr, newcap, item_size);
+        if (!newptr) {
+            return NULL;
+        }
+
+        *pcap = newcap;
+        return newptr;
+    }
+
+    // Copy the current content to the new array
+    //
+    // As an example, here is the content of a ring-buffer (oldcap=10) before
+    // the realloc:
+    //
+    //     5 6 7 _ _ 0 1 2 3 4
+    //               ^
+    //               origin
+    //
+    // It is resized (newcap=15), e.g. with sc_vecdeque_reserve():
+    //
+    //     0 1 2 3 4 5 6 7 _ _ _ _ _ _ _
+    //     ^
+    //     origin
+
+    assert(size);
+    void *newptr = sc_allocarray(newcap, item_size);
+    if (!newptr) {
+        return NULL;
+    }
+
+    size_t right_len = MIN(size, oldcap - oldorigin);
+    assert(right_len);
+    memcpy(newptr, ptr + (oldorigin * item_size), right_len * item_size);
+
+    if (size > right_len) {
+        memcpy(newptr + (right_len * item_size), ptr,
+               (size - right_len) * item_size);
+    }
+
+    free(ptr);
+
+    *pcap = newcap;
+    *porigin = 0;
+    return newptr;
+}
+
+/**
+ * Macro to realloc the internal data to a new capacity
+ *
+ * Private.
+ *
+ * \retval true on success
+ * \retval false on allocation failure (the VecDeque is left untouched)
+ */
+#define sc_vecdeque_realloc_(pv, newcap) \
+({ \
+    void *p = sc_vecdeque_reallocdata_((pv)->data, newcap, \
+                                       sizeof(*(pv)->data), &(pv)->cap, \
+                                       &(pv)->origin, (pv)->size); \
+    if (p) { \
+        (pv)->data = p; \
+    } \
+    (bool) p; \
+});
+
+static inline size_t
+sc_vecdeque_growsize_(size_t value)
+{
+    /* integer multiplication by 1.5 */
+    return value + (value >> 1);
+}
+
+/**
+ * Increase the capacity of the VecDeque to at least `mincap`
+ *
+ * \param pv a pointer to the VecDeque
+ * \param mincap (`size_t`) the requested capacity
+ * \retval true on success
+ * \retval false on allocation failure (the VecDeque is left untouched)
+ */
+#define sc_vecdeque_reserve(pv, mincap) \
+({ \
+    assert(mincap <= sc_vecdeque_max_cap_(pv)); \
+    bool ok; \
+    /* avoid to allocate tiny arrays (< SC_VECDEQUE_MINCAP_) */ \
+    size_t mincap_ = MAX(mincap, SC_VECDEQUE_MINCAP_); \
+    if (mincap_ <= (pv)->cap) { \
+        /* nothing to do */ \
+        ok = true; \
+    } else if (mincap_ <= sc_vecdeque_max_cap_(pv)) { \
+        /* not too big */ \
+        size_t newsize = sc_vecdeque_growsize_((pv)->cap); \
+        newsize = CLAMP(newsize, mincap_, sc_vecdeque_max_cap_(pv)); \
+        ok = sc_vecdeque_realloc_(pv, newsize); \
+    } else { \
+        ok = false; \
+    } \
+    ok; \
+})
+
+/**
+ * Automatically grow the VecDeque capacity
+ *
+ * Private.
+ *
+ * \retval true on success
+ * \retval false on allocation failure (the VecDeque is left untouched)
+ */
+#define sc_vecdeque_grow_(pv) \
+({ \
+    bool ok; \
+    if ((pv)->cap < sc_vecdeque_max_cap_(pv)) { \
+        size_t newsize = sc_vecdeque_growsize_((pv)->cap); \
+        newsize = CLAMP(newsize, SC_VECDEQUE_MINCAP_, \
+                        sc_vecdeque_max_cap_(pv)); \
+        ok = sc_vecdeque_realloc_(pv, newsize); \
+    } else { \
+        ok = false; \
+    } \
+    ok; \
+})
+
+/**
+ * Grow the VecDeque capacity if it is full
+ *
+ * Private.
+ *
+ * \retval true on success
+ * \retval false on allocation failure (the VecDeque is left untouched)
+ */
+#define sc_vecdeque_grow_if_needed_(pv) \
+    (!sc_vecdeque_is_full(pv) || sc_vecdeque_grow_(pv))
+
+/**
+ * Push an uninitialized item, and return a pointer to it
+ *
+ * It does not attempt to resize the VecDeque. It is an error to this function
+ * if the VecDeque is full.
+ *
+ * This function may not fail. It returns a valid non-NULL pointer to the
+ * uninitialized item just pushed.
+ */
+#define sc_vecdeque_push_hole_noresize(pv) \
+({ \
+    assert(!sc_vecdeque_is_full(pv)); \
+    ++(pv)->size; \
+    &(pv)->data[((pv)->origin + (pv)->size - 1) % (pv)->cap]; \
+})
+
+/**
+ * Push an uninitialized item, and return a pointer to it
+ *
+ * If the VecDeque is full, it is resized.
+ *
+ * This function returns either a valid non-NULL pointer to the uninitialized
+ * item just pushed, or NULL on reallocation failure.
+ */
+#define sc_vecdeque_push_hole(pv) \
+    (sc_vecdeque_grow_if_needed_(pv) ? \
+            sc_vecdeque_push_hole_noresize(pv) : NULL)
+
+/**
+ * Push an item
+ *
+ * It does not attempt to resize the VecDeque. It is an error to this function
+ * if the VecDeque is full.
+ *
+ * This function may not fail.
+ */
+#define sc_vecdeque_push_noresize(pv, item) \
+(void) ({ \
+    assert(!sc_vecdeque_is_full(pv)); \
+    ++(pv)->size; \
+    (pv)->data[((pv)->origin + (pv)->size - 1) % (pv)->cap] = item; \
+})
+
+/**
+ * Push an item
+ *
+ * If the VecDeque is full, it is resized.
+ *
+ * \retval true on success
+ * \retval false on allocation failure (the VecDeque is left untouched)
+ */
+#define sc_vecdeque_push(pv, item) \
+({ \
+    bool ok = sc_vecdeque_grow_if_needed_(pv); \
+    if (ok) { \
+        sc_vecdeque_push_noresize(pv, item); \
+    } \
+    ok; \
+})
+
+/**
+ * Pop an item and return a pointer to it (still in the VecDeque)
+ *
+ * Returning a pointer allows the caller to destroy it in place without copy
+ * (especially if the item type is big).
+ *
+ * It is an error to call this function if the VecDeque is empty.
+ */
+#define sc_vecdeque_popref(pv) \
+({ \
+    assert(!sc_vecdeque_is_empty(pv)); \
+    size_t pos = (pv)->origin; \
+    (pv)->origin = ((pv)->origin + 1) % (pv)->cap; \
+    --(pv)->size; \
+    &(pv)->data[pos]; \
+})
+
+/**
+ * Pop an item and return it
+ *
+ * It is an error to call this function if the VecDeque is empty.
+ */
+#define sc_vecdeque_pop(pv) \
+    (*sc_vecdeque_popref(pv))
+
+#endif

app/src/util/vector.h

@@ -118,7 +118,7 @@ static inline void *
 sc_vector_reallocdata_(void *ptr, size_t count, size_t size,
                         size_t *restrict pcap, size_t *restrict psize)
 {
-    void *p = realloc(ptr, count * size);
+    void *p = reallocarray(ptr, count, size);
     if (!p) {
         return NULL;
     }

app/src/v4l2_sink.c

@@ -126,7 +126,7 @@ run_v4l2_sink(void *data) {
         vs->has_frame = false;
         sc_mutex_unlock(&vs->mutex);
 
-        sc_video_buffer_consume(&vs->vb, vs->frame);
+        sc_frame_buffer_consume(&vs->fb, vs->frame);
 
         bool ok = encode_and_write_frame(vs, vs->frame);
         av_frame_unref(vs->frame);
@@ -141,42 +141,19 @@ run_v4l2_sink(void *data) {
     return 0;
 }
 
-static void
-sc_video_buffer_on_new_frame(struct sc_video_buffer *vb, bool previous_skipped,
-                             void *userdata) {
-    (void) vb;
-    struct sc_v4l2_sink *vs = userdata;
-
-    if (!previous_skipped) {
-        sc_mutex_lock(&vs->mutex);
-        vs->has_frame = true;
-        sc_cond_signal(&vs->cond);
-        sc_mutex_unlock(&vs->mutex);
-    }
-}
-
 static bool
 sc_v4l2_sink_open(struct sc_v4l2_sink *vs, const AVCodecContext *ctx) {
     assert(ctx->pix_fmt == AV_PIX_FMT_YUV420P);
     (void) ctx;
 
-    static const struct sc_video_buffer_callbacks cbs = {
-        .on_new_frame = sc_video_buffer_on_new_frame,
-    };
-
-    bool ok = sc_video_buffer_init(&vs->vb, vs->buffering_time, &cbs, vs);
+    bool ok = sc_frame_buffer_init(&vs->fb);
     if (!ok) {
         return false;
     }
 
-    ok = sc_video_buffer_start(&vs->vb);
-    if (!ok) {
-        goto error_video_buffer_destroy;
-    }
-
     ok = sc_mutex_init(&vs->mutex);
     if (!ok) {
-        goto error_video_buffer_stop_and_join;
+        goto error_frame_buffer_destroy;
     }
 
     ok = sc_cond_init(&vs->cond);
@@ -228,11 +205,13 @@ sc_v4l2_sink_open(struct sc_v4l2_sink *vs, const AVCodecContext *ctx) {
         goto error_avformat_free_context;
     }
 
-    ostream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+    int r = avcodec_parameters_from_context(ostream->codecpar, ctx);
+    if (r < 0) {
+        goto error_avformat_free_context;
+    }
+
+    // The codec is from the v4l2 encoder, not from the decoder
     ostream->codecpar->codec_id = encoder->id;
-    ostream->codecpar->format = AV_PIX_FMT_YUV420P;
-    ostream->codecpar->width = vs->frame_size.width;
-    ostream->codecpar->height = vs->frame_size.height;
 
     int ret = avio_open(&vs->format_ctx->pb, vs->device_name, AVIO_FLAG_WRITE);
     if (ret < 0) {
@@ -247,8 +226,8 @@ sc_v4l2_sink_open(struct sc_v4l2_sink *vs, const AVCodecContext *ctx) {
         goto error_avio_close;
     }
 
-    vs->encoder_ctx->width = vs->frame_size.width;
-    vs->encoder_ctx->height = vs->frame_size.height;
+    vs->encoder_ctx->width = ctx->width;
+    vs->encoder_ctx->height = ctx->height;
     vs->encoder_ctx->pix_fmt = AV_PIX_FMT_YUV420P;
     vs->encoder_ctx->time_base.num = 1;
     vs->encoder_ctx->time_base.den = 1;
@@ -301,11 +280,8 @@ error_cond_destroy:
     sc_cond_destroy(&vs->cond);
 error_mutex_destroy:
     sc_mutex_destroy(&vs->mutex);
-error_video_buffer_stop_and_join:
-    sc_video_buffer_stop(&vs->vb);
-    sc_video_buffer_join(&vs->vb);
-error_video_buffer_destroy:
-    sc_video_buffer_destroy(&vs->vb);
+error_frame_buffer_destroy:
+    sc_frame_buffer_destroy(&vs->fb);
 
     return false;
 }
@@ -317,10 +293,7 @@ sc_v4l2_sink_close(struct sc_v4l2_sink *vs) {
     sc_cond_signal(&vs->cond);
     sc_mutex_unlock(&vs->mutex);
 
-    sc_video_buffer_stop(&vs->vb);
-
     sc_thread_join(&vs->thread, NULL);
-    sc_video_buffer_join(&vs->vb);
 
     av_packet_free(&vs->packet);
     av_frame_free(&vs->frame);
@@ -330,12 +303,25 @@ sc_v4l2_sink_close(struct sc_v4l2_sink *vs) {
     avformat_free_context(vs->format_ctx);
     sc_cond_destroy(&vs->cond);
     sc_mutex_destroy(&vs->mutex);
-    sc_video_buffer_destroy(&vs->vb);
+    sc_frame_buffer_destroy(&vs->fb);
 }
 
 static bool
 sc_v4l2_sink_push(struct sc_v4l2_sink *vs, const AVFrame *frame) {
-    return sc_video_buffer_push(&vs->vb, frame);
+    bool previous_skipped;
+    bool ok = sc_frame_buffer_push(&vs->fb, frame, &previous_skipped);
+    if (!ok) {
+        return false;
+    }
+
+    if (!previous_skipped) {
+        sc_mutex_lock(&vs->mutex);
+        vs->has_frame = true;
+        sc_cond_signal(&vs->cond);
+        sc_mutex_unlock(&vs->mutex);
+    }
+
+    return true;
 }
 
 static bool
@@ -357,17 +343,13 @@ sc_v4l2_frame_sink_push(struct sc_frame_sink *sink, const AVFrame *frame) {
 }
 
 bool
-sc_v4l2_sink_init(struct sc_v4l2_sink *vs, const char *device_name,
-                  struct sc_size frame_size, sc_tick buffering_time) {
+sc_v4l2_sink_init(struct sc_v4l2_sink *vs, const char *device_name) {
     vs->device_name = strdup(device_name);
     if (!vs->device_name) {
         LOGE("Could not strdup v4l2 device name");
         return false;
     }
 
-    vs->frame_size = frame_size;
-    vs->buffering_time = buffering_time;
-
     static const struct sc_frame_sink_ops ops = {
         .open = sc_v4l2_frame_sink_open,
         .close = sc_v4l2_frame_sink_close,

app/src/v4l2_sink.h

@@ -8,19 +8,17 @@
 
 #include "coords.h"
 #include "trait/frame_sink.h"
-#include "video_buffer.h"
+#include "frame_buffer.h"
 #include "util/tick.h"
 
 struct sc_v4l2_sink {
     struct sc_frame_sink frame_sink; // frame sink trait
 
-    struct sc_video_buffer vb;
+    struct sc_frame_buffer fb;
     AVFormatContext *format_ctx;
     AVCodecContext *encoder_ctx;
 
     char *device_name;
-    struct sc_size frame_size;
-    sc_tick buffering_time;
 
     sc_thread thread;
     sc_mutex mutex;
@@ -34,8 +32,7 @@ struct sc_v4l2_sink {
 };
 
 bool
-sc_v4l2_sink_init(struct sc_v4l2_sink *vs, const char *device_name,
-                  struct sc_size frame_size, sc_tick buffering_time);
+sc_v4l2_sink_init(struct sc_v4l2_sink *vs, const char *device_name);
 
 void
 sc_v4l2_sink_destroy(struct sc_v4l2_sink *vs);

app/src/video_buffer.c

@@ -1,254 +0,0 @@
-#include "video_buffer.h"
-
-#include <assert.h>
-#include <stdlib.h>
-
-#include <libavutil/avutil.h>
-#include <libavformat/avformat.h>
-
-#include "util/log.h"
-
-#define SC_BUFFERING_NDEBUG // comment to debug
-
-static struct sc_video_buffer_frame *
-sc_video_buffer_frame_new(const AVFrame *frame) {
-    struct sc_video_buffer_frame *vb_frame = malloc(sizeof(*vb_frame));
-    if (!vb_frame) {
-        LOG_OOM();
-        return NULL;
-    }
-
-    vb_frame->frame = av_frame_alloc();
-    if (!vb_frame->frame) {
-        LOG_OOM();
-        free(vb_frame);
-        return NULL;
-    }
-
-    if (av_frame_ref(vb_frame->frame, frame)) {
-        av_frame_free(&vb_frame->frame);
-        free(vb_frame);
-        return NULL;
-    }
-
-    return vb_frame;
-}
-
-static void
-sc_video_buffer_frame_delete(struct sc_video_buffer_frame *vb_frame) {
-    av_frame_unref(vb_frame->frame);
-    av_frame_free(&vb_frame->frame);
-    free(vb_frame);
-}
-
-static bool
-sc_video_buffer_offer(struct sc_video_buffer *vb, const AVFrame *frame) {
-    bool previous_skipped;
-    bool ok = sc_frame_buffer_push(&vb->fb, frame, &previous_skipped);
-    if (!ok) {
-        return false;
-    }
-
-    vb->cbs->on_new_frame(vb, previous_skipped, vb->cbs_userdata);
-    return true;
-}
-
-static int
-run_buffering(void *data) {
-    struct sc_video_buffer *vb = data;
-
-    assert(vb->buffering_time > 0);
-
-    for (;;) {
-        sc_mutex_lock(&vb->b.mutex);
-
-        while (!vb->b.stopped && sc_queue_is_empty(&vb->b.queue)) {
-            sc_cond_wait(&vb->b.queue_cond, &vb->b.mutex);
-        }
-
-        if (vb->b.stopped) {
-            sc_mutex_unlock(&vb->b.mutex);
-            goto stopped;
-        }
-
-        struct sc_video_buffer_frame *vb_frame;
-        sc_queue_take(&vb->b.queue, next, &vb_frame);
-
-        sc_tick max_deadline = sc_tick_now() + vb->buffering_time;
-        // PTS (written by the server) are expressed in microseconds
-        sc_tick pts = SC_TICK_TO_US(vb_frame->frame->pts);
-
-        bool timed_out = false;
-        while (!vb->b.stopped && !timed_out) {
-            sc_tick deadline = sc_clock_to_system_time(&vb->b.clock, pts)
-                             + vb->buffering_time;
-            if (deadline > max_deadline) {
-                deadline = max_deadline;
-            }
-
-            timed_out =
-                !sc_cond_timedwait(&vb->b.wait_cond, &vb->b.mutex, deadline);
-        }
-
-        if (vb->b.stopped) {
-            sc_video_buffer_frame_delete(vb_frame);
-            sc_mutex_unlock(&vb->b.mutex);
-            goto stopped;
-        }
-
-        sc_mutex_unlock(&vb->b.mutex);
-
-#ifndef SC_BUFFERING_NDEBUG
-        LOGD("Buffering: %" PRItick ";%" PRItick ";%" PRItick,
-             pts, vb_frame->push_date, sc_tick_now());
-#endif
-
-        sc_video_buffer_offer(vb, vb_frame->frame);
-
-        sc_video_buffer_frame_delete(vb_frame);
-    }
-
-stopped:
-    // Flush queue
-    while (!sc_queue_is_empty(&vb->b.queue)) {
-        struct sc_video_buffer_frame *vb_frame;
-        sc_queue_take(&vb->b.queue, next, &vb_frame);
-        sc_video_buffer_frame_delete(vb_frame);
-    }
-
-    LOGD("Buffering thread ended");
-
-    return 0;
-}
-
-bool
-sc_video_buffer_init(struct sc_video_buffer *vb, sc_tick buffering_time,
-                     const struct sc_video_buffer_callbacks *cbs,
-                     void *cbs_userdata) {
-    bool ok = sc_frame_buffer_init(&vb->fb);
-    if (!ok) {
-        return false;
-    }
-
-    assert(buffering_time >= 0);
-    if (buffering_time) {
-        ok = sc_mutex_init(&vb->b.mutex);
-        if (!ok) {
-            sc_frame_buffer_destroy(&vb->fb);
-            return false;
-        }
-
-        ok = sc_cond_init(&vb->b.queue_cond);
-        if (!ok) {
-            sc_mutex_destroy(&vb->b.mutex);
-            sc_frame_buffer_destroy(&vb->fb);
-            return false;
-        }
-
-        ok = sc_cond_init(&vb->b.wait_cond);
-        if (!ok) {
-            sc_cond_destroy(&vb->b.queue_cond);
-            sc_mutex_destroy(&vb->b.mutex);
-            sc_frame_buffer_destroy(&vb->fb);
-            return false;
-        }
-
-        sc_clock_init(&vb->b.clock);
-        sc_queue_init(&vb->b.queue);
-    }
-
-    assert(cbs);
-    assert(cbs->on_new_frame);
-
-    vb->buffering_time = buffering_time;
-    vb->cbs = cbs;
-    vb->cbs_userdata = cbs_userdata;
-    return true;
-}
-
-bool
-sc_video_buffer_start(struct sc_video_buffer *vb) {
-    if (vb->buffering_time) {
-        bool ok =
-            sc_thread_create(&vb->b.thread, run_buffering, "scrcpy-vbuf", vb);
-        if (!ok) {
-            LOGE("Could not start buffering thread");
-            return false;
-        }
-    }
-
-    return true;
-}
-
-void
-sc_video_buffer_stop(struct sc_video_buffer *vb) {
-    if (vb->buffering_time) {
-        sc_mutex_lock(&vb->b.mutex);
-        vb->b.stopped = true;
-        sc_cond_signal(&vb->b.queue_cond);
-        sc_cond_signal(&vb->b.wait_cond);
-        sc_mutex_unlock(&vb->b.mutex);
-    }
-}
-
-void
-sc_video_buffer_join(struct sc_video_buffer *vb) {
-    if (vb->buffering_time) {
-        sc_thread_join(&vb->b.thread, NULL);
-    }
-}
-
-void
-sc_video_buffer_destroy(struct sc_video_buffer *vb) {
-    sc_frame_buffer_destroy(&vb->fb);
-    if (vb->buffering_time) {
-        sc_cond_destroy(&vb->b.wait_cond);
-        sc_cond_destroy(&vb->b.queue_cond);
-        sc_mutex_destroy(&vb->b.mutex);
-    }
-}
-
-bool
-sc_video_buffer_push(struct sc_video_buffer *vb, const AVFrame *frame) {
-    if (!vb->buffering_time) {
-        // No buffering
-        return sc_video_buffer_offer(vb, frame);
-    }
-
-    sc_mutex_lock(&vb->b.mutex);
-
-    sc_tick pts = SC_TICK_FROM_US(frame->pts);
-    sc_clock_update(&vb->b.clock, sc_tick_now(), pts);
-    sc_cond_signal(&vb->b.wait_cond);
-
-    if (vb->b.clock.count == 1) {
-        sc_mutex_unlock(&vb->b.mutex);
-        // First frame, offer it immediately, for two reasons:
-        //  - not to delay the opening of the scrcpy window
-        //  - the buffering estimation needs at least two clock points, so it
-        //  could not handle the first frame
-        return sc_video_buffer_offer(vb, frame);
-    }
-
-    struct sc_video_buffer_frame *vb_frame = sc_video_buffer_frame_new(frame);
-    if (!vb_frame) {
-        sc_mutex_unlock(&vb->b.mutex);
-        LOG_OOM();
-        return false;
-    }
-
-#ifndef SC_BUFFERING_NDEBUG
-    vb_frame->push_date = sc_tick_now();
-#endif
-    sc_queue_push(&vb->b.queue, next, vb_frame);
-    sc_cond_signal(&vb->b.queue_cond);
-
-    sc_mutex_unlock(&vb->b.mutex);
-
-    return true;
-}
-
-void
-sc_video_buffer_consume(struct sc_video_buffer *vb, AVFrame *dst) {
-    sc_frame_buffer_consume(&vb->fb, dst);
-}

app/src/video_buffer.h

@@ -1,76 +0,0 @@
-#ifndef SC_VIDEO_BUFFER_H
-#define SC_VIDEO_BUFFER_H
-
-#include "common.h"
-
-#include <stdbool.h>
-
-#include "clock.h"
-#include "frame_buffer.h"
-#include "util/queue.h"
-#include "util/thread.h"
-#include "util/tick.h"
-
-// forward declarations
-typedef struct AVFrame AVFrame;
-
-struct sc_video_buffer_frame {
-    AVFrame *frame;
-    struct sc_video_buffer_frame *next;
-#ifndef NDEBUG
-    sc_tick push_date;
-#endif
-};
-
-struct sc_video_buffer_frame_queue SC_QUEUE(struct sc_video_buffer_frame);
-
-struct sc_video_buffer {
-    struct sc_frame_buffer fb;
-
-    sc_tick buffering_time;
-
-    // only if buffering_time > 0
-    struct {
-        sc_thread thread;
-        sc_mutex mutex;
-        sc_cond queue_cond;
-        sc_cond wait_cond;
-
-        struct sc_clock clock;
-        struct sc_video_buffer_frame_queue queue;
-        bool stopped;
-    } b; // buffering
-
-    const struct sc_video_buffer_callbacks *cbs;
-    void *cbs_userdata;
-};
-
-struct sc_video_buffer_callbacks {
-    void (*on_new_frame)(struct sc_video_buffer *vb, bool previous_skipped,
-                         void *userdata);
-};
-
-bool
-sc_video_buffer_init(struct sc_video_buffer *vb, sc_tick buffering_time,
-                     const struct sc_video_buffer_callbacks *cbs,
-                     void *cbs_userdata);
-
-bool
-sc_video_buffer_start(struct sc_video_buffer *vb);
-
-void
-sc_video_buffer_stop(struct sc_video_buffer *vb);
-
-void
-sc_video_buffer_join(struct sc_video_buffer *vb);
-
-void
-sc_video_buffer_destroy(struct sc_video_buffer *vb);
-
-bool
-sc_video_buffer_push(struct sc_video_buffer *vb, const AVFrame *frame);
-
-void
-sc_video_buffer_consume(struct sc_video_buffer *vb, AVFrame *dst);
-
-#endif

app/tests/test_bytebuf.c

@@ -13,23 +13,23 @@ void test_bytebuf_simple(void) {
     assert(ok);
 
     sc_bytebuf_write(&buf, (uint8_t *) "hello", sizeof("hello") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 5);
+    assert(sc_bytebuf_can_read(&buf) == 5);
 
     sc_bytebuf_read(&buf, data, 4);
     assert(!strncmp((char *) data, "hell", 4));
 
     sc_bytebuf_write(&buf, (uint8_t *) " world", sizeof(" world") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 7);
+    assert(sc_bytebuf_can_read(&buf) == 7);
 
     sc_bytebuf_write(&buf, (uint8_t *) "!", 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 8);
+    assert(sc_bytebuf_can_read(&buf) == 8);
 
     sc_bytebuf_read(&buf, &data[4], 8);
-    assert(sc_bytebuf_read_remaining(&buf) == 0);
+    assert(sc_bytebuf_can_read(&buf) == 0);
 
     data[12] = '\0';
     assert(!strcmp((char *) data, "hello world!"));
-    assert(sc_bytebuf_read_remaining(&buf) == 0);
+    assert(sc_bytebuf_can_read(&buf) == 0);
 
     sc_bytebuf_destroy(&buf);
 }
@@ -42,58 +42,31 @@ void test_bytebuf_boundaries(void) {
     assert(ok);
 
     sc_bytebuf_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 6);
+    assert(sc_bytebuf_can_read(&buf) == 6);
 
     sc_bytebuf_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 12);
+    assert(sc_bytebuf_can_read(&buf) == 12);
 
     sc_bytebuf_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 18);
+    assert(sc_bytebuf_can_read(&buf) == 18);
 
     sc_bytebuf_read(&buf, data, 9);
     assert(!strncmp((char *) data, "hello hel", 9));
-    assert(sc_bytebuf_read_remaining(&buf) == 9);
+    assert(sc_bytebuf_can_read(&buf) == 9);
 
     sc_bytebuf_write(&buf, (uint8_t *) "world", sizeof("world") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 14);
+    assert(sc_bytebuf_can_read(&buf) == 14);
 
     sc_bytebuf_write(&buf, (uint8_t *) "!", 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 15);
+    assert(sc_bytebuf_can_read(&buf) == 15);
 
     sc_bytebuf_skip(&buf, 3);
-    assert(sc_bytebuf_read_remaining(&buf) == 12);
+    assert(sc_bytebuf_can_read(&buf) == 12);
 
     sc_bytebuf_read(&buf, data, 12);
     data[12] = '\0';
     assert(!strcmp((char *) data, "hello world!"));
-    assert(sc_bytebuf_read_remaining(&buf) == 0);
-
-    sc_bytebuf_destroy(&buf);
-}
-
-void test_bytebuf_overwrite(void) {
-    struct sc_bytebuf buf;
-    uint8_t data[10];
-
-    bool ok = sc_bytebuf_init(&buf, 10); // so actual capacity is 9
-    assert(ok);
-
-    sc_bytebuf_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 6);
-
-    sc_bytebuf_write(&buf, (uint8_t *) "abcdef", sizeof("abcdef") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 9);
-
-    sc_bytebuf_read(&buf, data, 9);
-    assert(!strncmp((char *) data, "lo abcdef", 9));
-
-    sc_bytebuf_write(&buf, (uint8_t *) "a very big buffer",
-                     sizeof("a very big buffer") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 9);
-
-    sc_bytebuf_read(&buf, data, 9);
-    assert(!strncmp((char *) data, "ig buffer", 9));
-    assert(sc_bytebuf_read_remaining(&buf) == 0);
+    assert(sc_bytebuf_can_read(&buf) == 0);
 
     sc_bytebuf_destroy(&buf);
 }
@@ -106,37 +79,37 @@ void test_bytebuf_two_steps_write(void) {
     assert(ok);
 
     sc_bytebuf_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 6);
+    assert(sc_bytebuf_can_read(&buf) == 6);
 
     sc_bytebuf_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 12);
+    assert(sc_bytebuf_can_read(&buf) == 12);
 
     sc_bytebuf_prepare_write(&buf, (uint8_t *) "hello ", sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 12); // write not committed yet
+    assert(sc_bytebuf_can_read(&buf) == 12); // write not committed yet
 
     sc_bytebuf_read(&buf, data, 9);
     assert(!strncmp((char *) data, "hello hel", 3));
-    assert(sc_bytebuf_read_remaining(&buf) == 3);
+    assert(sc_bytebuf_can_read(&buf) == 3);
 
     sc_bytebuf_commit_write(&buf, sizeof("hello ") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 9);
+    assert(sc_bytebuf_can_read(&buf) == 9);
 
     sc_bytebuf_prepare_write(&buf, (uint8_t *) "world", sizeof("world") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 9); // write not committed yet
+    assert(sc_bytebuf_can_read(&buf) == 9); // write not committed yet
 
     sc_bytebuf_commit_write(&buf, sizeof("world") - 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 14);
+    assert(sc_bytebuf_can_read(&buf) == 14);
 
     sc_bytebuf_write(&buf, (uint8_t *) "!", 1);
-    assert(sc_bytebuf_read_remaining(&buf) == 15);
+    assert(sc_bytebuf_can_read(&buf) == 15);
 
     sc_bytebuf_skip(&buf, 3);
-    assert(sc_bytebuf_read_remaining(&buf) == 12);
+    assert(sc_bytebuf_can_read(&buf) == 12);
 
     sc_bytebuf_read(&buf, data, 12);
     data[12] = '\0';
     assert(!strcmp((char *) data, "hello world!"));
-    assert(sc_bytebuf_read_remaining(&buf) == 0);
+    assert(sc_bytebuf_can_read(&buf) == 0);
 
     sc_bytebuf_destroy(&buf);
 }
@@ -147,7 +120,6 @@ int main(int argc, char *argv[]) {
 
     test_bytebuf_simple();
     test_bytebuf_boundaries();
-    test_bytebuf_overwrite();
     test_bytebuf_two_steps_write();
 
     return 0;

app/tests/test_cbuf.c

@@ -1,78 +0,0 @@
-#include "common.h"
-
-#include <assert.h>
-#include <string.h>
-
-#include "util/cbuf.h"
-
-struct int_queue CBUF(int, 32);
-
-static void test_cbuf_empty(void) {
-    struct int_queue queue;
-    cbuf_init(&queue);
-
-    assert(cbuf_is_empty(&queue));
-
-    bool push_ok = cbuf_push(&queue, 42);
-    assert(push_ok);
-    assert(!cbuf_is_empty(&queue));
-
-    int item;
-    bool take_ok = cbuf_take(&queue, &item);
-    assert(take_ok);
-    assert(cbuf_is_empty(&queue));
-
-    bool take_empty_ok = cbuf_take(&queue, &item);
-    assert(!take_empty_ok); // the queue is empty
-}
-
-static void test_cbuf_full(void) {
-    struct int_queue queue;
-    cbuf_init(&queue);
-
-    assert(!cbuf_is_full(&queue));
-
-    // fill the queue
-    for (int i = 0; i < 32; ++i) {
-        bool ok = cbuf_push(&queue, i);
-        assert(ok);
-    }
-    bool ok = cbuf_push(&queue, 42);
-    assert(!ok); // the queue if full
-
-    int item;
-    bool take_ok = cbuf_take(&queue, &item);
-    assert(take_ok);
-    assert(!cbuf_is_full(&queue));
-}
-
-static void test_cbuf_push_take(void) {
-    struct int_queue queue;
-    cbuf_init(&queue);
-
-    bool push1_ok = cbuf_push(&queue, 42);
-    assert(push1_ok);
-
-    bool push2_ok = cbuf_push(&queue, 35);
-    assert(push2_ok);
-
-    int item;
-
-    bool take1_ok = cbuf_take(&queue, &item);
-    assert(take1_ok);
-    assert(item == 42);
-
-    bool take2_ok = cbuf_take(&queue, &item);
-    assert(take2_ok);
-    assert(item == 35);
-}
-
-int main(int argc, char *argv[]) {
-    (void) argc;
-    (void) argv;
-
-    test_cbuf_empty();
-    test_cbuf_full();
-    test_cbuf_push_take();
-    return 0;
-}

app/tests/test_queue.c

@@ -1,43 +0,0 @@
-#include "common.h"
-
-#include <assert.h>
-
-#include "util/queue.h"
-
-struct foo {
-    int value;
-    struct foo *next;
-};
-
-static void test_queue(void) {
-    struct my_queue SC_QUEUE(struct foo) queue;
-    sc_queue_init(&queue);
-
-    assert(sc_queue_is_empty(&queue));
-
-    struct foo v1 = { .value = 42 };
-    struct foo v2 = { .value = 27 };
-
-    sc_queue_push(&queue, next, &v1);
-    sc_queue_push(&queue, next, &v2);
-
-    struct foo *foo;
-
-    assert(!sc_queue_is_empty(&queue));
-    sc_queue_take(&queue, next, &foo);
-    assert(foo->value == 42);
-
-    assert(!sc_queue_is_empty(&queue));
-    sc_queue_take(&queue, next, &foo);
-    assert(foo->value == 27);
-
-    assert(sc_queue_is_empty(&queue));
-}
-
-int main(int argc, char *argv[]) {
-    (void) argc;
-    (void) argv;
-
-    test_queue();
-    return 0;
-}

app/tests/test_vecdeque.c

@@ -0,0 +1,197 @@
+#include "common.h"
+
+#include <assert.h>
+
+#include "util/vecdeque.h"
+
+#define pr(pv) \
+({ \
+    fprintf(stderr, "cap=%lu origin=%lu size=%lu\n", (pv)->cap, (pv)->origin, (pv)->size); \
+    for (size_t i = 0; i < (pv)->cap; ++i) \
+        fprintf(stderr, "%d ", (pv)->data[i]); \
+    fprintf(stderr, "\n"); \
+})
+
+static void test_vecdeque_push_pop(void) {
+    struct SC_VECDEQUE(int) vdq = SC_VECDEQUE_INITIALIZER;
+
+    assert(sc_vecdeque_is_empty(&vdq));
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    bool ok = sc_vecdeque_push(&vdq, 5);
+    assert(ok);
+    assert(sc_vecdeque_size(&vdq) == 1);
+
+    ok = sc_vecdeque_push(&vdq, 12);
+    assert(ok);
+    assert(sc_vecdeque_size(&vdq) == 2);
+
+    int v = sc_vecdeque_pop(&vdq);
+    assert(v == 5);
+    assert(sc_vecdeque_size(&vdq) == 1);
+
+    ok = sc_vecdeque_push(&vdq, 7);
+    assert(ok);
+    assert(sc_vecdeque_size(&vdq) == 2);
+
+    int *p = sc_vecdeque_popref(&vdq);
+    assert(p);
+    assert(*p == 12);
+    assert(sc_vecdeque_size(&vdq) == 1);
+
+    v = sc_vecdeque_pop(&vdq);
+    assert(v == 7);
+    assert(sc_vecdeque_size(&vdq) == 0);
+    assert(sc_vecdeque_is_empty(&vdq));
+
+    sc_vecdeque_destroy(&vdq);
+}
+
+static void test_vecdeque_reserve(void) {
+    struct SC_VECDEQUE(int) vdq = SC_VECDEQUE_INITIALIZER;
+
+    bool ok = sc_vecdeque_reserve(&vdq, 20);
+    assert(ok);
+    assert(vdq.cap == 20);
+
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    for (size_t i = 0; i < 20; ++i) {
+        ok = sc_vecdeque_push(&vdq, i);
+        assert(ok);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 20);
+
+    // It is now full
+
+    for (int i = 0; i < 5; ++i) {
+        int v = sc_vecdeque_pop(&vdq);
+        assert(v == i);
+    }
+    assert(sc_vecdeque_size(&vdq) == 15);
+
+    for (int i = 20; i < 25; ++i) {
+        ok = sc_vecdeque_push(&vdq, i);
+        assert(ok);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 20);
+    assert(vdq.cap == 20);
+
+    // Now, the content wraps around the ring buffer:
+    // 20 21 22 23 24  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19
+    //                 ^
+    //                 origin
+
+    // It is now full, let's reserve some space
+    ok = sc_vecdeque_reserve(&vdq, 30);
+    assert(ok);
+    assert(vdq.cap == 30);
+
+    assert(sc_vecdeque_size(&vdq) == 20);
+
+    for (int i = 0; i < 20; ++i) {
+        // We should retrieve the items we inserted in order
+        int v = sc_vecdeque_pop(&vdq);
+        assert(v == i + 5);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    sc_vecdeque_destroy(&vdq);
+}
+
+static void test_vecdeque_grow() {
+    struct SC_VECDEQUE(int) vdq = SC_VECDEQUE_INITIALIZER;
+
+    bool ok = sc_vecdeque_reserve(&vdq, 20);
+    assert(ok);
+    assert(vdq.cap == 20);
+
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    for (int i = 0; i < 500; ++i) {
+        ok = sc_vecdeque_push(&vdq, i);
+        assert(ok);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 500);
+
+    for (int i = 0; i < 100; ++i) {
+        int v = sc_vecdeque_pop(&vdq);
+        assert(v == i);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 400);
+
+    for (int i = 500; i < 1000; ++i) {
+        ok = sc_vecdeque_push(&vdq, i);
+        assert(ok);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 900);
+
+    for (int i = 100; i < 1000; ++i) {
+        int v = sc_vecdeque_pop(&vdq);
+        assert(v == i);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    sc_vecdeque_destroy(&vdq);
+}
+
+static void test_vecdeque_push_hole() {
+    struct SC_VECDEQUE(int) vdq = SC_VECDEQUE_INITIALIZER;
+
+    bool ok = sc_vecdeque_reserve(&vdq, 20);
+    assert(ok);
+    assert(vdq.cap == 20);
+
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    for (int i = 0; i < 20; ++i) {
+        int *p = sc_vecdeque_push_hole(&vdq);
+        assert(p);
+        *p = i * 10;
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 20);
+
+    for (int i = 0; i < 10; ++i) {
+        int v = sc_vecdeque_pop(&vdq);
+        assert(v == i * 10);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 10);
+
+    for (int i = 20; i < 30; ++i) {
+        int *p = sc_vecdeque_push_hole(&vdq);
+        assert(p);
+        *p = i * 10;
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 20);
+
+    for (int i = 10; i < 30; ++i) {
+        int v = sc_vecdeque_pop(&vdq);
+        assert(v == i * 10);
+    }
+
+    assert(sc_vecdeque_size(&vdq) == 0);
+
+    sc_vecdeque_destroy(&vdq);
+}
+
+int main(int argc, char *argv[]) {
+    (void) argc;
+    (void) argv;
+
+    test_vecdeque_push_pop();
+    test_vecdeque_reserve();
+    test_vecdeque_grow();
+    test_vecdeque_push_hole();
+
+    return 0;
+}

cross_win32.txt

@@ -16,6 +16,6 @@ cpu = 'i686'
 endian = 'little'
 
 [properties]
-prebuilt_ffmpeg = 'ffmpeg-6.0-scrcpy/win32'
-prebuilt_sdl2 = 'SDL2-2.26.1/i686-w64-mingw32'
+prebuilt_ffmpeg = 'ffmpeg-6.0-scrcpy-2/win32'
+prebuilt_sdl2 = 'SDL2-2.26.4/i686-w64-mingw32'
 prebuilt_libusb = 'libusb-1.0.26/libusb-MinGW-Win32'

cross_win64.txt

@@ -16,6 +16,6 @@ cpu = 'x86_64'
 endian = 'little'
 
 [properties]
-prebuilt_ffmpeg = 'ffmpeg-6.0-scrcpy/win64'
-prebuilt_sdl2 = 'SDL2-2.26.1/x86_64-w64-mingw32'
+prebuilt_ffmpeg = 'ffmpeg-6.0-scrcpy-2/win64'
+prebuilt_sdl2 = 'SDL2-2.26.4/x86_64-w64-mingw32'
 prebuilt_libusb = 'libusb-1.0.26/libusb-MinGW-x64'

doc/audio.md

@@ -0,0 +1,101 @@
+# Audio
+
+Audio forwarding is supported for devices with Android 11 or higher, and it is
+enabled by default:
+
+ - For **Android 12 or newer**, it works out-of-the-box.
+ - For **Android 11**, you'll need to ensure that the device screen is unlocked
+   when starting scrcpy. A fake popup will briefly appear to make the system
+   think that the shell app is in the foreground. Without this, audio capture
+   will fail.
+ - For **Android 10 or earlier**, audio cannot be captured and is automatically
+   disabled.
+
+If audio capture fails, then mirroring continues with video only (since audio is
+enabled by default, it is not acceptable to make scrcpy fail if it is not
+available), unless `--require-audio` is set.
+
+
+## No audio
+
+To disable audio:
+
+```
+scrcpy --no-audio
+```
+
+## Codec
+
+The audio codec can be selected. The possible values are `opus` (default), `aac`
+and `raw` (uncompressed PCM 16-bit LE):
+
+```bash
+scrcpy --audio-codec=opus  # default
+scrcpy --audio-codec=aac
+scrcpy --audio-codec=raw
+```
+
+Several encoders may be available on the device. They can be listed by:
+
+```bash
+scrcpy --list-encoders
+```
+
+To select a specific encoder:
+
+```
+scrcpy --audio-codec=opus --audio-encoder='c2.android.opus.encoder'
+```
+
+For advanced usage, to pass arbitrary parameters to the [`MediaFormat`],
+check `--audio-codec-options` in the manpage or in `scrcpy --help`.
+
+[`MediaFormat`]: https://developer.android.com/reference/android/media/MediaFormat
+
+
+## Bit rate
+
+The default video bit-rate is 128Kbps. To change it:
+
+```bash
+scrcpy --audio-bit-rate=64K
+scrcpy --audio-bit-rate=64000  # equivalent
+```
+
+_This parameter does not apply to RAW audio codec (`--audio-codec=raw`)._
+
+
+## Buffering
+
+Audio buffering is unavoidable. It must be kept small enough so that the latency
+is acceptable, but large enough to minimize buffer underrun (causing audio
+glitches).
+
+The default buffer size is set to 50ms. It can be adjusted:
+
+```bash
+scrcpy --audio-buffer=40   # smaller than default
+scrcpy --audio-buffer=100  # higher than default
+```
+
+Note that this option changes the _target_ buffering. It is possible that this
+target buffering might not be reached (on frequent buffer underflow typically).
+
+If you don't interact with the device (to watch a video for example), a higher
+latency (for both [video](video.md#buffering) and audio) might be preferable to
+avoid glitches and smooth the playback:
+
+```
+scrcpy --display-buffer=200 --audio-buffer=200
+```
+
+It is also possible to configure another audio buffer (the audio output buffer),
+by default set to 5ms. Don't change it, unless you get some [robotic and glitchy
+sound][#3793]:
+
+```bash
+# Only if absolutely necessary
+scrcpy --audio-output-buffer=10
+```
+
+[#3793]: https://github.com/Genymobile/scrcpy/issues/3793

doc/build.md

@@ -2,57 +2,16 @@
 
 Here are the instructions to build _scrcpy_ (client and server).
 
-
-## Simple
-
-If you just want to install the latest release from `master`, follow this
-simplified process.
-
-First, you need to install the required packages:
-
-```bash
-# for Debian/Ubuntu
-sudo apt install ffmpeg libsdl2-2.0-0 adb wget \
-                 gcc git pkg-config meson ninja-build libsdl2-dev \
-                 libavcodec-dev libavdevice-dev libavformat-dev libavutil-dev \
-                 libusb-1.0-0 libusb-1.0-0-dev
-```
-
-Then clone the repo and execute the installation script
-([source](install_release.sh)):
-
-```bash
-git clone https://github.com/Genymobile/scrcpy
-cd scrcpy
-./install_release.sh
-```
-
-When a new release is out, update the repo and reinstall:
-
-```bash
-git pull
-./install_release.sh
-```
-
-To uninstall:
-
-```bash
-sudo ninja -Cbuild-auto uninstall
-```
-
+If you just want to build and install the latest release, follow the simplified
+process described in [doc/linux.md](linux.md).
 
 ## Branches
 
-### `master`
-
-The `master` branch concerns the latest release, and is the home page of the
-project on GitHub.
-
-
-### `dev`
-
-`dev` is the current development branch. Every commit present in `dev` will be
-in the next release.
+There are two main branches:
+ - `master`: contains the latest release. It is the home page of the project on
+   GitHub.
+ - `dev`: the current development branch. Every commit present in `dev` will be
+   in the next release.
 
 If you want to contribute code, please base your commits on the latest `dev`
 branch.
@@ -69,6 +28,8 @@ the following files to a directory accessible from your `PATH`:
  - `AdbWinApi.dll`
  - `AdbWinUsbApi.dll`
 
+It is also available in scrcpy releases.
+
 The client requires [FFmpeg] and [LibSDL2]. Just follow the instructions.
 
 [adb]: https://developer.android.com/studio/command-line/adb.html
@@ -94,7 +55,7 @@ sudo apt install ffmpeg libsdl2-2.0-0 adb libusb-1.0-0
 # client build dependencies
 sudo apt install gcc git pkg-config meson ninja-build libsdl2-dev \
                  libavcodec-dev libavdevice-dev libavformat-dev libavutil-dev \
-                 libusb-1.0-0-dev
+                 libswresample-dev libusb-1.0-0-dev
 
 # server build dependencies
 sudo apt install openjdk-11-jdk
@@ -272,10 +233,10 @@ install` must be run as root)._
 
 #### Option 2: Use prebuilt server
 
- - [`scrcpy-server-v1.25`][direct-scrcpy-server]  
-   <sub>SHA-256: `ce0306c7bbd06ae72f6d06f7ec0ee33774995a65de71e0a83813ecb67aec9bdb`</sub>
+ - [`scrcpy-server-v2.0`][direct-scrcpy-server]  
+   <sub>SHA-256: `9e241615f578cd690bb43311000debdecf6a9c50a7082b001952f18f6f21ddc2`</sub>
 
-[direct-scrcpy-server]: https://github.com/Genymobile/scrcpy/releases/download/v1.25/scrcpy-server-v1.25
+[direct-scrcpy-server]: https://github.com/Genymobile/scrcpy/releases/download/v2.0/scrcpy-server-v2.0
 
 Download the prebuilt server somewhere, and specify its path during the Meson
 configuration:
@@ -314,7 +275,8 @@ This installs several files:
  - `/usr/local/share/zsh/site-functions/_scrcpy` (zsh completion)
  - `/usr/local/share/bash-completion/completions/scrcpy` (bash completion)
 
-You can then [run](README.md#run) `scrcpy`.
+You can then run `scrcpy`.
+
 
 ### Uninstall
 

doc/control.md

@@ -0,0 +1,149 @@
+# Control
+
+## Read-only
+
+To disable controls (everything which can interact with the device: input keys,
+mouse events, drag&drop files):
+
+```bash
+scrcpy --no-control
+scrcpy -n   # short version
+```
+
+
+## Text injection preference
+
+Two kinds of [events][textevents] are generated when typing text:
+ - _key events_, signaling that a key is pressed or released;
+ - _text events_, signaling that a text has been entered.
+
+By default, letters are injected using key events, so that the keyboard behaves
+as expected in games (typically for WASD keys).
+
+But this may [cause issues][prefertext]. If you encounter such a problem, you
+can avoid it by:
+
+```bash
+scrcpy --prefer-text
+```
+
+(but this will break keyboard behavior in games)
+
+On the contrary, you could force to always inject raw key events:
+
+```bash
+scrcpy --raw-key-events
+```
+
+These options have no effect on HID keyboard (all key events are sent as
+scancodes in this mode).
+
+[textevents]: https://blog.rom1v.com/2018/03/introducing-scrcpy/#handle-text-input
+[prefertext]: https://github.com/Genymobile/scrcpy/issues/650#issuecomment-512945343
+
+
+## Copy-paste
+
+Any time the Android clipboard changes, it is automatically synchronized to the
+computer clipboard.
+
+Any <kbd>Ctrl</kbd> shortcut is forwarded to the device. In particular:
+ - <kbd>Ctrl</kbd>+<kbd>c</kbd> typically copies
+ - <kbd>Ctrl</kbd>+<kbd>x</kbd> typically cuts
+ - <kbd>Ctrl</kbd>+<kbd>v</kbd> typically pastes (after computer-to-device
+   clipboard synchronization)
+
+This typically works as you expect.
+
+The actual behavior depends on the active application though. For example,
+_Termux_ sends SIGINT on <kbd>Ctrl</kbd>+<kbd>c</kbd> instead, and _K-9 Mail_
+composes a new message.
+
+To copy, cut and paste in such cases (but only supported on Android >= 7):
+ - <kbd>MOD</kbd>+<kbd>c</kbd> injects `COPY`
+ - <kbd>MOD</kbd>+<kbd>x</kbd> injects `CUT`
+ - <kbd>MOD</kbd>+<kbd>v</kbd> injects `PASTE` (after computer-to-device
+   clipboard synchronization)
+
+In addition, <kbd>MOD</kbd>+<kbd>Shift</kbd>+<kbd>v</kbd> injects the computer
+clipboard text as a sequence of key events. This is useful when the component
+does not accept text pasting (for example in _Termux_), but it can break
+non-ASCII content.
+
+**WARNING:** Pasting the computer clipboard to the device (either via
+<kbd>Ctrl</kbd>+<kbd>v</kbd> or <kbd>MOD</kbd>+<kbd>v</kbd>) copies the content
+into the Android clipboard. As a consequence, any Android application could read
+its content. You should avoid pasting sensitive content (like passwords) that
+way.
+
+Some Android devices do not behave as expected when setting the device clipboard
+programmatically. An option `--legacy-paste` is provided to change the behavior
+of <kbd>Ctrl</kbd>+<kbd>v</kbd> and <kbd>MOD</kbd>+<kbd>v</kbd> so that they
+also inject the computer clipboard text as a sequence of key events (the same
+way as <kbd>MOD</kbd>+<kbd>Shift</kbd>+<kbd>v</kbd>).
+
+To disable automatic clipboard synchronization, use
+`--no-clipboard-autosync`.
+
+## Pinch-to-zoom
+
+To simulate "pinch-to-zoom": <kbd>Ctrl</kbd>+_click-and-move_.
+
+More precisely, hold down <kbd>Ctrl</kbd> while pressing the left-click button.
+Until the left-click button is released, all mouse movements scale and rotate
+the content (if supported by the app) relative to the center of the screen.
+
+Technically, _scrcpy_ generates additional touch events from a "virtual finger"
+at a location inverted through the center of the screen.
+
+
+## Key repeat
+
+By default, holding a key down generates repeated key events. This can cause
+performance problems in some games, where these events are useless anyway.
+
+To avoid forwarding repeated key events:
+
+```bash
+scrcpy --no-key-repeat
+```
+
+This option has no effect on HID keyboard (key repeat is handled by Android
+directly in this mode).
+
+
+## Right-click and middle-click
+
+By default, right-click triggers BACK (or POWER on) and middle-click triggers
+HOME. To disable these shortcuts and forward the clicks to the device instead:
+
+```bash
+scrcpy --forward-all-clicks
+```
+
+## File drop
+
+### Install APK
+
+To install an APK, drag & drop an APK file (ending with `.apk`) to the _scrcpy_
+window.
+
+There is no visual feedback, a log is printed to the console.
+
+
+### Push file to device
+
+To push a file to `/sdcard/Download/` on the device, drag & drop a (non-APK)
+file to the _scrcpy_ window.
+
+There is no visual feedback, a log is printed to the console.
+
+The target directory can be changed on start:
+
+```bash
+scrcpy --push-target=/sdcard/Movies/
+```
+
+## Physical keyboard and mouse simulation
+
+See the dedicated [HID/OTG](hid-otg.md) page.

doc/device.md

@@ -0,0 +1,228 @@
+# Device
+
+## Selection
+
+If exactly one device is connected (i.e. listed by `adb devices`), then it is
+automatically selected.
+
+However, if there are multiple devices connected, you must specify the one to
+use in one of 4 ways:
+ - by its serial:
+   ```bash
+   scrcpy --serial=0123456789abcdef
+   scrcpy -s 0123456789abcdef   # short version
+
+   # the serial is the ip:port if connected over TCP/IP (same behavior as adb)
+   scrcpy --serial=192.168.1.1:5555
+   ```
+ - the one connected over USB (if there is exactly one):
+   ```bash
+   scrcpy --select-usb
+   scrcpy -d   # short version
+   ```
+ - the one connected over TCP/IP (if there is exactly one):
+   ```bash
+   scrcpy --select-tcpip
+   scrcpy -e   # short version
+   ```
+ - a device already listening on TCP/IP (see [below](#tcpip-wireless)):
+   ```bash
+   scrcpy --tcpip=192.168.1.1:5555
+   scrcpy --tcpip=192.168.1.1        # default port is 5555
+   ```
+
+The serial may also be provided via the environment variable `ANDROID_SERIAL`
+(also used by `adb`):
+
+```bash
+# in bash
+export ANDROID_SERIAL=0123456789abcdef
+scrcpy
+```
+
+```cmd
+:: in cmd
+set ANDROID_SERIAL=0123456789abcdef
+scrcpy
+```
+
+```powershell
+# in PowerShell
+$env:ANDROID_SERIAL = '0123456789abcdef'
+scrcpy
+```
+
+
+## TCP/IP (wireless)
+
+_Scrcpy_ uses `adb` to communicate with the device, and `adb` can [connect] to a
+device over TCP/IP. The device must be connected on the same network as the
+computer.
+
+[connect]: https://developer.android.com/studio/command-line/adb.html#wireless
+
+
+### Automatic
+
+An option `--tcpip` allows to configure the connection automatically. There are
+two variants.
+
+If the device (accessible at 192.168.1.1 in this example) already listens on a
+port (typically 5555) for incoming _adb_ connections, then run:
+
+```bash
+scrcpy --tcpip=192.168.1.1       # default port is 5555
+scrcpy --tcpip=192.168.1.1:5555
+```
+
+If _adb_ TCP/IP mode is disabled on the device (or if you don't know the IP
+address), connect the device over USB, then run:
+
+```bash
+scrcpy --tcpip   # without arguments
+```
+
+It will automatically find the device IP address and adb port, enable TCP/IP
+mode if necessary, then connect to the device before starting.
+
+
+### Manual
+
+Alternatively, it is possible to enable the TCP/IP connection manually using
+`adb`:
+
+1. Plug the device into a USB port on your computer.
+2. Connect the device to the same Wi-Fi network as your computer.
+3. Get your device IP address, in Settings → About phone → Status, or by
+   executing this command:
+
+    ```bash
+    adb shell ip route | awk '{print $9}'
+    ```
+
+4. Enable `adb` over TCP/IP on your device: `adb tcpip 5555`.
+5. Unplug your device.
+6. Connect to your device: `adb connect DEVICE_IP:5555` _(replace `DEVICE_IP`
+with the device IP address you found)_.
+7. Run `scrcpy` as usual.
+8. Run `adb disconnect` once you're done.
+
+Since Android 11, a [wireless debugging option][adb-wireless] allows to bypass
+having to physically connect your device directly to your computer.
+
+[adb-wireless]: https://developer.android.com/studio/command-line/adb#wireless-android11-command-line
+
+
+## Autostart
+
+A small tool (by the scrcpy author) allows to run arbitrary commands whenever a
+new Android device is connected: [AutoAdb]. It can be used to start scrcpy:
+
+```bash
+autoadb scrcpy -s '{}'
+```
+
+[AutoAdb]: https://github.com/rom1v/autoadb
+
+
+## Display
+
+If several displays are available on the Android device, it is possible to
+select the display to mirror:
+
+```bash
+scrcpy --display=1
+```
+
+The list of display ids can be retrieved by:
+
+```bash
+scrcpy --list-displays
+```
+
+A secondary display may only be controlled if the device runs at least Android
+10 (otherwise it is mirrored as read-only).
+
+
+## Actions
+
+Some command line arguments perform actions on the device itself while scrcpy is
+running.
+
+
+### Stay awake
+
+To prevent the device from sleeping after a delay **when the device is plugged
+in**:
+
+```bash
+scrcpy --stay-awake
+scrcpy -w
+```
+
+The initial state is restored when _scrcpy_ is closed.
+
+If the device is not plugged in (i.e. only connected over TCP/IP),
+`--stay-awake` has no effect (this is the Android behavior).
+
+
+### Turn screen off
+
+It is possible to turn the device screen off while mirroring on start with a
+command-line option:
+
+```bash
+scrcpy --turn-screen-off
+scrcpy -S   # short version
+```
+
+Or by pressing <kbd>MOD</kbd>+<kbd>o</kbd> at any time (see
+[shortcuts](shortcuts.md)).
+
+To turn it back on, press <kbd>MOD</kbd>+<kbd>Shift</kbd>+<kbd>o</kbd>.
+
+On Android, the `POWER` button always turns the screen on. For convenience, if
+`POWER` is sent via _scrcpy_ (via right-click or <kbd>MOD</kbd>+<kbd>p</kbd>),
+it will force to turn the screen off after a small delay (on a best effort
+basis). The physical `POWER` button will still cause the screen to be turned on.
+
+It can also be useful to prevent the device from sleeping:
+
+```bash
+scrcpy --turn-screen-off --stay-awake
+scrcpy -Sw   # short version
+```
+
+
+### Show touches
+
+For presentations, it may be useful to show physical touches (on the physical
+device). Android exposes this feature in _Developers options_.
+
+_Scrcpy_ provides an option to enable this feature on start and restore the
+initial value on exit:
+
+```bash
+scrcpy --show-touches
+scrcpy -t   # short version
+```
+
+Note that it only shows _physical_ touches (by a finger on the device).
+
+
+### Power off on close
+
+To turn the device screen off when closing _scrcpy_:
+
+```bash
+scrcpy --power-off-on-close
+```
+
+### Power on on start
+
+By default, on start, the device is powered on. To prevent this behavior:
+
+```bash
+scrcpy --no-power-on
+```
+

doc/hid-otg.md

@@ -0,0 +1,108 @@
+# HID/OTG
+
+By default, _scrcpy_ injects input events at the Android API level. As an
+alternative, when connected over USB, it is possible to send HID events, so that
+scrcpy behaves as if it was a physical keyboard and/or mouse connected to the
+Android device.
+
+A special [OTG](#otg) mode allows to control the device without mirroring (and
+without USB debugging).
+
+
+## Physical keyboard simulation
+
+By default, _scrcpy_ uses Android key or text injection. It works everywhere,
+but is limited to ASCII.
+
+Instead, it can simulate a physical USB keyboard on Android to provide a better
+input experience (using [USB HID over AOAv2][hid-aoav2]): the virtual keyboard
+is disabled and it works for all characters and IME.
+
+[hid-aoav2]: https://source.android.com/devices/accessories/aoa2#hid-support
+
+However, it only works if the device is connected via USB.
+
+Note: On Windows, it may only work in [OTG mode](#otg), not while mirroring (it
+is not possible to open a USB device if it is already open by another process
+like the _adb daemon_).
+
+To enable this mode:
+
+```bash
+scrcpy --hid-keyboard
+scrcpy -K   # short version
+```
+
+If it fails for some reason (for example because the device is not connected via
+USB), it automatically fallbacks to the default mode (with a log in the
+console). This allows using the same command line options when connected over
+USB and TCP/IP.
+
+In this mode, raw key events (scancodes) are sent to the device, independently
+of the host key mapping. Therefore, if your keyboard layout does not match, it
+must be configured on the Android device, in Settings → System → Languages and
+input → [Physical keyboard].
+
+This settings page can be started directly:
+
+```bash
+adb shell am start -a android.settings.HARD_KEYBOARD_SETTINGS
+```
+
+However, the option is only available when the HID keyboard is enabled (or when
+a physical keyboard is connected).
+
+[Physical keyboard]: https://github.com/Genymobile/scrcpy/pull/2632#issuecomment-923756915
+
+
+## Physical mouse simulation
+
+By default, _scrcpy_ uses Android mouse events injection with absolute
+coordinates. By simulating a physical mouse, a mouse pointer appears on the
+Android device, and relative mouse motion, clicks and scrolls are injected.
+
+To enable this mode:
+
+```bash
+scrcpy --hid-mouse
+scrcpy -M   # short version
+```
+
+When this mode is enabled, the computer mouse is "captured" (the mouse pointer
+disappears from the computer and appears on the Android device instead).
+
+Special capture keys, either <kbd>Alt</kbd> or <kbd>Super</kbd>, toggle
+(disable or enable) the mouse capture. Use one of them to give the control of
+the mouse back to the computer.
+
+
+## OTG
+
+It is possible to run _scrcpy_ with only physical keyboard and mouse simulation
+(HID), as if the computer keyboard and mouse were plugged directly to the device
+via an OTG cable.
+
+In this mode, `adb` (USB debugging) is not necessary, and mirroring is disabled.
+
+This is similar to `--hid-keyboard --hid-mouse`, but without mirroring.
+
+To enable OTG mode:
+
+```bash
+scrcpy --otg
+# Pass the serial if several USB devices are available
+scrcpy --otg -s 0123456789abcdef
+```
+
+It is possible to enable only HID keyboard or HID mouse:
+
+```bash
+scrcpy --otg --hid-keyboard              # keyboard only
+scrcpy --otg --hid-mouse                 # mouse only
+scrcpy --otg --hid-keyboard --hid-mouse  # keyboard and mouse
+# for convenience, enable both by default
+scrcpy --otg                             # keyboard and mouse
+```
+
+Like `--hid-keyboard` and `--hid-mouse`, it only works if the device is
+connected over USB.

doc/linux.md

@@ -0,0 +1,81 @@
+# On Linux
+
+## Install
+
+<a href="https://repology.org/project/scrcpy/versions"><img src="https://repology.org/badge/vertical-allrepos/scrcpy.svg" alt="Packaging status" align="right"></a>
+
+Scrcpy is packaged in several distributions and package managers:
+
+ - Debian/Ubuntu: `apt install scrcpy`
+ - Arch Linux: `pacman -S scrcpy`
+ - Fedora: `dnf copr enable zeno/scrcpy && dnf install scrcpy`
+ - Gentoo: [ebuild][ebuild-link] file
+ - Snap: `snap install scrcpy`
+ - … (see [repology](https://repology.org/project/scrcpy/versions))
+
+[ebuild-link]: https://github.com/maggu2810/maggu2810-overlay/tree/master/app-mobilephone/scrcpy
+
+### Latest version
+
+However, the packaged version is not always the latest release. To install the
+latest release from `master`, follow this simplified process.
+
+First, you need to install the required packages:
+
+```bash
+# for Debian/Ubuntu
+sudo apt install ffmpeg libsdl2-2.0-0 adb wget \
+                 gcc git pkg-config meson ninja-build libsdl2-dev \
+                 libavcodec-dev libavdevice-dev libavformat-dev libavutil-dev \
+                 libswresample-dev libusb-1.0-0 libusb-1.0-0-dev
+```
+
+Then clone the repo and execute the installation script
+([source](/install_release.sh)):
+
+```bash
+git clone https://github.com/Genymobile/scrcpy
+cd scrcpy
+./install_release.sh
+```
+
+When a new release is out, update the repo and reinstall:
+
+```bash
+git pull
+./install_release.sh
+```
+
+To uninstall:
+
+```bash
+sudo ninja -Cbuild-auto uninstall
+```
+
+_Note that this simplified process only works for released versions (it
+downloads a prebuilt server binary), so for example you can't use it for testing
+the development branch (`dev`)._
+
+_See [build.md](build.md) to build and install the app manually._
+
+
+## Run
+
+_Make sure that your device meets the [prerequisites](/README.md#prerequisites)._
+
+Once installed, run from a terminal:
+
+```bash
+scrcpy
+```
+
+or with arguments (here to disable audio and record to `file.mkv`):
+
+```bash
+scrcpy --no-audio --record=file.mkv
+```
+
+Documentation for command line arguments is available:
+ - `man scrcpy`
+ - `scrcpy --help`
+ - on [github](/README.md)

doc/macos.md

@@ -0,0 +1,49 @@
+# On macOS
+
+## Install
+
+Scrcpy is available in [Homebrew]:
+
+```bash
+brew install scrcpy
+```
+
+[Homebrew]: https://brew.sh/
+
+You need `adb`, accessible from your `PATH`. If you don't have it yet:
+
+```bash
+brew install android-platform-tools
+```
+
+Alternatively, Scrcpy is also available in [MacPorts], which sets up `adb` for you:
+
+```bash
+sudo port install scrcpy
+```
+
+[MacPorts]: https://www.macports.org/
+
+_See [build.md](build.md) to build and install the app manually._
+
+
+## Run
+
+_Make sure that your device meets the [prerequisites](/README.md#prerequisites)._
+
+Once installed, run from a terminal:
+
+```bash
+scrcpy
+```
+
+or with arguments (here to disable audio and record to `file.mkv`):
+
+```bash
+scrcpy --no-audio --record=file.mkv
+```
+
+Documentation for command line arguments is available:
+ - `man scrcpy`
+ - `scrcpy --help`
+ - on [github](/README.md)

doc/recording.md

@@ -0,0 +1,44 @@
+# Recording
+
+To record video and audio streams while mirroring:
+
+```bash
+scrcpy --record=file.mp4
+scrcpy -r file.mkv
+```
+
+To record only the video:
+
+```bash
+scrcpy --no-audio --record=file.mp4
+```
+
+_It is currently not possible to record only the audio._
+
+To disable mirroring while recording:
+
+```bash
+scrcpy --no-display --record=file.mp4
+scrcpy -Nr file.mkv
+# interrupt recording with Ctrl+C
+```
+
+Timestamps are captured on the device, so [packet delay variation] does not
+impact the recorded file, which is always clean (only if you use `--record` of
+course, not if you capture your scrcpy window and audio output on the computer).
+
+[packet delay variation]: https://en.wikipedia.org/wiki/Packet_delay_variation
+
+The video and audio streams are encoded on the device, but are muxed on the
+client side. Two formats (containers) are supported:
+ - Matroska (`.mkv`)
+ - MP4 (`.mp4`)
+
+The container is automatically selected based on the filename.
+
+It is also possible to explicitly select a container (in that case the filename
+needs not end with `.mkv` or `.mp4`):
+
+```
+scrcpy --record=file --record-format=mkv
+```

doc/shortcuts.md

@@ -0,0 +1,68 @@
+# Shortcuts
+
+Actions can be performed on the scrcpy window using keyboard and mouse
+shortcuts.
+
+In the following list, <kbd>MOD</kbd> is the shortcut modifier. By default, it's
+(left) <kbd>Alt</kbd> or (left) <kbd>Super</kbd>.
+
+It can be changed using `--shortcut-mod`. Possible keys are `lctrl`, `rctrl`,
+`lalt`, `ralt`, `lsuper` and `rsuper`. For example:
+
+```bash
+# use RCtrl for shortcuts
+scrcpy --shortcut-mod=rctrl
+
+# use either LCtrl+LAlt or LSuper for shortcuts
+scrcpy --shortcut-mod=lctrl+lalt,lsuper
+```
+
+_<kbd>[Super]</kbd> is typically the <kbd>Windows</kbd> or <kbd>Cmd</kbd> key._
+
+[Super]: https://en.wikipedia.org/wiki/Super_key_(keyboard_button)
+
+ | Action                                      |   Shortcut
+ | ------------------------------------------- |:-----------------------------
+ | Switch fullscreen mode                      | <kbd>MOD</kbd>+<kbd>f</kbd>
+ | Rotate display left                         | <kbd>MOD</kbd>+<kbd>←</kbd> _(left)_
+ | Rotate display right                        | <kbd>MOD</kbd>+<kbd>→</kbd> _(right)_
+ | Resize window to 1:1 (pixel-perfect)        | <kbd>MOD</kbd>+<kbd>g</kbd>
+ | Resize window to remove black borders       | <kbd>MOD</kbd>+<kbd>w</kbd> \| _Double-left-click¹_
+ | Click on `HOME`                             | <kbd>MOD</kbd>+<kbd>h</kbd> \| _Middle-click_
+ | Click on `BACK`                             | <kbd>MOD</kbd>+<kbd>b</kbd> \| _Right-click²_
+ | Click on `APP_SWITCH`                       | <kbd>MOD</kbd>+<kbd>s</kbd> \| _4th-click³_
+ | Click on `MENU` (unlock screen)⁴            | <kbd>MOD</kbd>+<kbd>m</kbd>
+ | Click on `VOLUME_UP`                        | <kbd>MOD</kbd>+<kbd>↑</kbd> _(up)_
+ | Click on `VOLUME_DOWN`                      | <kbd>MOD</kbd>+<kbd>↓</kbd> _(down)_
+ | Click on `POWER`                            | <kbd>MOD</kbd>+<kbd>p</kbd>
+ | Power on                                    | _Right-click²_
+ | Turn device screen off (keep mirroring)     | <kbd>MOD</kbd>+<kbd>o</kbd>
+ | Turn device screen on                       | <kbd>MOD</kbd>+<kbd>Shift</kbd>+<kbd>o</kbd>
+ | Rotate device screen                        | <kbd>MOD</kbd>+<kbd>r</kbd>
+ | Expand notification panel                   | <kbd>MOD</kbd>+<kbd>n</kbd> \| _5th-click³_
+ | Expand settings panel                       | <kbd>MOD</kbd>+<kbd>n</kbd>+<kbd>n</kbd> \| _Double-5th-click³_
+ | Collapse panels                             | <kbd>MOD</kbd>+<kbd>Shift</kbd>+<kbd>n</kbd>
+ | Copy to clipboard⁵                          | <kbd>MOD</kbd>+<kbd>c</kbd>
+ | Cut to clipboard⁵                           | <kbd>MOD</kbd>+<kbd>x</kbd>
+ | Synchronize clipboards and paste⁵           | <kbd>MOD</kbd>+<kbd>v</kbd>
+ | Inject computer clipboard text              | <kbd>MOD</kbd>+<kbd>Shift</kbd>+<kbd>v</kbd>
+ | Enable/disable FPS counter (on stdout)      | <kbd>MOD</kbd>+<kbd>i</kbd>
+ | Pinch-to-zoom                               | <kbd>Ctrl</kbd>+_click-and-move_
+ | Drag & drop APK file                        | Install APK from computer
+ | Drag & drop non-APK file                    | [Push file to device](control.md#push-file-to-device)
+
+_¹Double-click on black borders to remove them._  
+_²Right-click turns the screen on if it was off, presses BACK otherwise._  
+_³4th and 5th mouse buttons, if your mouse has them._  
+_⁴For react-native apps in development, `MENU` triggers development menu._  
+_⁵Only on Android >= 7._
+
+Shortcuts with repeated keys are executed by releasing and pressing the key a
+second time. For example, to execute "Expand settings panel":
+
+ 1. Press and keep pressing <kbd>MOD</kbd>.
+ 2. Then double-press <kbd>n</kbd>.
+ 3. Finally, release <kbd>MOD</kbd>.
+
+All <kbd>Ctrl</kbd>+_key_ shortcuts are forwarded to the device, so they are
+handled by the active application.

doc/tunnels.md

@@ -0,0 +1,123 @@
+# Tunnels
+
+Scrcpy is designed to mirror local Android devices. Tunnels allow to connect to
+a remote device (e.g. over the Internet).
+
+To connect to a remote device, it is possible to connect a local `adb` client to
+a remote `adb` server (provided they use the same version of the _adb_
+protocol).
+
+
+## Remote ADB server
+
+To connect to a remote _adb server_, make the server listen on all interfaces:
+
+```bash
+adb kill-server
+adb -a nodaemon server start
+# keep this open
+```
+
+**Warning: all communications between clients and the _adb server_ are
+unencrypted.**
+
+Suppose that this server is accessible at 192.168.1.2. Then, from another
+terminal, run `scrcpy`:
+
+```bash
+# in bash
+export ADB_SERVER_SOCKET=tcp:192.168.1.2:5037
+scrcpy --tunnel-host=192.168.1.2
+```
+
+```cmd
+:: in cmd
+set ADB_SERVER_SOCKET=tcp:192.168.1.2:5037
+scrcpy --tunnel-host=192.168.1.2
+```
+
+```powershell
+# in PowerShell
+$env:ADB_SERVER_SOCKET = 'tcp:192.168.1.2:5037'
+scrcpy --tunnel-host=192.168.1.2
+```
+
+By default, `scrcpy` uses the local port used for `adb forward` tunnel
+establishment (typically `27183`, see `--port`). It is also possible to force a
+different tunnel port (it may be useful in more complex situations, when more
+redirections are involved):
+
+```
+scrcpy --tunnel-port=1234
+```
+
+
+## SSH tunnel
+
+To communicate with a remote _adb server_ securely, it is preferable to use an
+SSH tunnel.
+
+First, make sure the _adb server_ is running on the remote computer:
+
+```bash
+adb start-server
+```
+
+Then, establish an SSH tunnel:
+
+```bash
+# local  5038 --> remote  5037
+# local 27183 <-- remote 27183
+ssh -CN -L5038:localhost:5037 -R27183:localhost:27183 your_remote_computer
+# keep this open
+```
+
+From another terminal, run `scrcpy`:
+
+```bash
+# in bash
+export ADB_SERVER_SOCKET=tcp:localhost:5038
+scrcpy
+```
+
+```cmd
+:: in cmd
+set ADB_SERVER_SOCKET=tcp:localhost:5038
+scrcpy
+```
+
+```powershell
+# in PowerShell
+$env:ADB_SERVER_SOCKET = 'tcp:localhost:5038'
+scrcpy
+```
+
+To avoid enabling remote port forwarding, you could force a forward connection
+instead (notice the `-L` instead of `-R`):
+
+```bash
+# local  5038 --> remote  5037
+# local 27183 --> remote 27183
+ssh -CN -L5038:localhost:5037 -L27183:localhost:27183 your_remote_computer
+# keep this open
+```
+
+From another terminal, run `scrcpy`:
+
+```bash
+# in bash
+export ADB_SERVER_SOCKET=tcp:localhost:5038
+scrcpy --force-adb-forward
+```
+
+```cmd
+:: in cmd
+set ADB_SERVER_SOCKET=tcp:localhost:5038
+scrcpy --force-adb-forward
+```
+
+```powershell
+# in PowerShell
+$env:ADB_SERVER_SOCKET = 'tcp:localhost:5038'
+scrcpy --force-adb-forward
+```

doc/v4l2.md

@@ -0,0 +1,65 @@
+# Video4Linux
+
+On Linux, it is possible to send the video stream to a [v4l2] loopback device,
+so that the Android device can be opened like a webcam by any v4l2-capable tool.
+
+[v4l2]: https://en.wikipedia.org/wiki/Video4Linux
+
+The module `v4l2loopback` must be installed:
+
+```bash
+sudo apt install v4l2loopback-dkms
+```
+
+To create a v4l2 device:
+
+```bash
+sudo modprobe v4l2loopback
+```
+
+This will create a new video device in `/dev/videoN`, where `N` is an integer
+(more [options](https://github.com/umlaeute/v4l2loopback#options) are available
+to create several devices or devices with specific IDs).
+
+To list the enabled devices:
+
+```bash
+# requires v4l-utils package
+v4l2-ctl --list-devices
+
+# simple but might be sufficient
+ls /dev/video*
+```
+
+To start `scrcpy` using a v4l2 sink:
+
+```bash
+scrcpy --v4l2-sink=/dev/videoN
+scrcpy --v4l2-sink=/dev/videoN --no-display  # disable mirroring window
+```
+
+(replace `N` with the device ID, check with `ls /dev/video*`)
+
+Once enabled, you can open your video stream with a v4l2-capable tool:
+
+```bash
+ffplay -i /dev/videoN
+vlc v4l2:///dev/videoN   # VLC might add some buffering delay
+```
+
+For example, you could capture the video within [OBS] or within your video
+conference tool.
+
+[OBS]: https://obsproject.com/
+
+
+## Buffering
+
+By default, there is no video buffering, to get the lowest possible latency.
+
+As for the [video display](video.md#buffering), it is possible to add
+buffering to delay the v4l2 stream:
+
+```bash
+scrcpy --v4l2-buffer=300     # add 300ms buffering for v4l2 sink
+```

doc/video.md

@@ -0,0 +1,175 @@
+# Video
+
+## Size
+
+By default, scrcpy attempts to mirror at the Android device resolution.
+
+It might be useful to mirror at a lower definition to increase performance. To
+limit both width and height to some maximum value (here 1024):
+
+```bash
+scrcpy --max-size=1024
+scrcpy -m 1024   # short version
+```
+
+The other dimension is computed so that the Android device aspect ratio is
+preserved. That way, a device in 1920×1080 will be mirrored at 1024×576.
+
+If encoding fails, scrcpy automatically tries again with a lower definition
+(unless `--no-downsize-on-error` is enabled).
+
+
+## Bit rate
+
+The default video bit-rate is 8 Mbps. To change it:
+
+```bash
+scrcpy --video-bit-rate=2M
+scrcpy --video-bit-rate=2000000  # equivalent
+scrcpy -b 2M                     # short version
+```
+
+
+## Frame rate
+
+The capture frame rate can be limited:
+
+```bash
+scrcpy --max-fps=15
+```
+
+The actual capture frame rate may be printed to the console:
+
+```
+scrcpy --print-fps
+```
+
+It may also be enabled or disabled at anytime with <kbd>MOD</kbd>+<kbd>i</kbd>
+(see [shortcuts](shortcuts.md)).
+
+The frame rate is intrinsically variable: a new frame is produced only when the
+screen content changes. For example, if you play a fullscreen video at 24fps on
+your device, you should not get more than 24 frames per second in scrcpy.
+
+
+## Codec
+
+The video codec can be selected. The possible values are `h264` (default),
+`h265` and `av1`:
+
+```bash
+scrcpy --video-codec=h264  # default
+scrcpy --video-codec=h265
+scrcpy --video-codec=av1
+```
+
+H265 may provide better quality, but H264 should provide lower latency.
+AV1 encoders are not common on current Android devices.
+
+Several encoders may be available on the device. They can be listed by:
+
+```bash
+scrcpy --list-encoders
+```
+
+Sometimes, the default encoder may have issues or even crash, so it is useful to
+try another one:
+
+```bash
+scrcpy --video-codec=h264 --video-encoder='OMX.qcom.video.encoder.avc'
+```
+
+For advanced usage, to pass arbitrary parameters to the [`MediaFormat`],
+check `--video-codec-options` in the manpage or in `scrcpy --help`.
+
+[`MediaFormat`]: https://developer.android.com/reference/android/media/MediaFormat
+
+
+## Rotation
+
+The rotation may be applied at 3 different levels:
+ - The [shortcut](shortcuts.md) <kbd>MOD</kbd>+<kbd>r</kbd> requests the
+   device to switch between portrait and landscape (the current running app may
+   refuse, if it does not support the requested orientation).
+ - `--lock-video-orientation` changes the mirroring orientation (the orientation
+   of the video sent from the device to the computer). This affects the
+   recording.
+ - `--rotation` rotates only the window content. This only affects the display,
+   not the recording. It may be changed dynamically at any time using the
+   [shortcuts](shortcuts.md) <kbd>MOD</kbd>+<kbd>←</kbd> and
+   <kbd>MOD</kbd>+<kbd>→</kbd>.
+
+To lock the mirroring orientation:
+
+```bash
+scrcpy --lock-video-orientation     # initial (current) orientation
+scrcpy --lock-video-orientation=0   # natural orientation
+scrcpy --lock-video-orientation=1   # 90° counterclockwise
+scrcpy --lock-video-orientation=2   # 180°
+scrcpy --lock-video-orientation=3   # 90° clockwise
+```
+
+To set an initial window rotation:
+
+```bash
+scrcpy --rotation=0   # no rotation
+scrcpy --rotation=1   # 90 degrees counterclockwise
+scrcpy --rotation=2   # 180 degrees
+scrcpy --rotation=3   # 90 degrees clockwise
+```
+
+## Crop
+
+The device screen may be cropped to mirror only part of the screen.
+
+This is useful, for example, to mirror only one eye of the Oculus Go:
+
+```bash
+scrcpy --crop=1224:1440:0:0   # 1224x1440 at offset (0,0)
+```
+
+The values are expressed in the device natural orientation (portrait for a
+phone, landscape for a tablet).
+
+If `--max-size` is also specified, resizing is applied after cropping.
+
+
+## Buffering
+
+By default, there is no video buffering, to get the lowest possible latency.
+
+Buffering can be added to delay the video stream and compensate for jitter to
+get a smoother playback (see [#2464]).
+
+[#2464]: https://github.com/Genymobile/scrcpy/issues/2464
+
+The configuration is available independently for the display,
+[v4l2 sinks](video.md#video4linux) and [audio](audio.md#buffering) playback.
+
+```bash
+scrcpy --display-buffer=50   # add 50ms buffering for display
+scrcpy --v4l2-buffer=300     # add 300ms buffering for v4l2 sink
+scrcpy --audio-buffer=200    # set 200ms buffering for audio playback
+```
+
+They can be applied simultaneously:
+
+```bash
+scrcpy --display-buffer=50 --v4l2-buffer=300
+```
+
+
+## No display
+
+It is possible to capture an Android device without displaying a mirroring
+window. This option is available if either [recording](recording.md) or
+[v4l2](#video4linux) is enabled:
+
+```bash
+scrcpy --v4l2-sink=/dev/video2 --no-display
+scrcpy --record=file.mkv --no-display
+```
+
+## Video4Linux
+
+See the dedicated [Video4Linux](v4l2.md) page.

doc/window.md

@@ -0,0 +1,55 @@
+# Window
+
+## Title
+
+By default, the window title is the device model. It can be changed:
+
+```bash
+scrcpy --window-title='My device'
+```
+
+## Position and size
+
+The initial window position and size may be specified:
+
+```bash
+scrcpy --window-x=100 --window-y=100 --window-width=800 --window-height=600
+```
+
+## Borderless
+
+To disable window decorations:
+
+```bash
+scrcpy --window-borderless
+```
+
+## Always on top
+
+To keep the window always on top:
+
+```bash
+scrcpy --always-on-top
+```
+
+## Fullscreen
+
+The app may be started directly in fullscreen:
+
+```bash
+scrcpy --fullscreen
+scrcpy -f   # short version
+```
+
+Fullscreen mode can then be toggled dynamically with <kbd>MOD</kbd>+<kbd>f</kbd>
+(see [shortcuts](shortcuts.md)).
+
+
+## Disable screensaver
+
+By default, _scrcpy_ does not prevent the screensaver from running on the
+computer. To disable it:
+
+```bash
+scrcpy --disable-screensaver
+```

doc/windows.md

@@ -0,0 +1,89 @@
+# On Windows
+
+## Install
+
+Download the [latest release]:
+
+ - [`scrcpy-win64-v2.0.zip`][direct-win64] (64-bit)  
+   <sub>SHA-256: `ae4c8d37a496b43f8974ba8f07f708e22a9570ba0cddc3dc3a36edbccd4d2a20`</sub>
+ - [`scrcpy-win32-v2.0.zip`][direct-win32] (32-bit)  
+   <sub>SHA-256: `15d98c02cb0e0bbd84f8b5d54991e0f6925569b1286a86a40743944fcb1c2d8c`</sub>
+
+[latest release]: https://github.com/Genymobile/scrcpy/releases/latest
+[direct-win64]: https://github.com/Genymobile/scrcpy/releases/download/v2.0/scrcpy-win64-v2.0.zip
+[direct-win32]: https://github.com/Genymobile/scrcpy/releases/download/v2.0/scrcpy-win32-v2.0.zip
+
+and extract it.
+
+Alternatively, you could install it from packages manager, like [Chocolatey]:
+
+```bash
+choco install scrcpy
+choco install adb    # if you don't have it yet
+```
+
+or [Scoop]:
+
+
+```bash
+scoop install scrcpy
+scoop install adb    # if you don't have it yet
+```
+
+[Chocolatey]: https://chocolatey.org/
+[Scoop]: https://scoop.sh
+
+_See [build.md](build.md) to build and install the app manually._
+
+
+## Run
+
+_Make sure that your device meets the [prerequisites](/README.md#prerequisites)._
+
+Scrcpy is a command line application: it is mainly intended to be executed from
+a terminal with command line arguments.
+
+To open a terminal at the expected location, double-click on
+`open_a_terminal_here.bat` in your scrcpy directory, then type your command. For
+example, without arguments:
+
+```bash
+scrcpy
+```
+
+or with arguments (here to disable audio and record to `file.mkv`):
+
+```
+scrcpy --no-audio --record=file.mkv
+```
+
+Documentation for command line arguments is available:
+ - `scrcpy --help`
+ - on [github](/README.md)
+
+To start scrcpy directly without opening a terminal, double-click on one of
+these files:
+ - `scrcpy-console.bat`: start with a terminal open (it will close when scrcpy
+   terminates, unless an error occurs);
+ - `scrcpy-noconsole.vbs`: start without a terminal (but you won't see any error
+   message).
+
+_Avoid double-clicking on `scrcpy.exe` directly: on error, the terminal would
+close immediately and you won't have time to read any error message (this
+executable is intended to be run from the terminal). Use `scrcpy-console.bat`
+instead._
+
+If you plan to always use the same arguments, create a file `myscrcpy.bat`
+(enable [show file extensions] to avoid confusion) containing your command, For
+example:
+
+```bash
+scrcpy --prefer-text --turn-screen-off --stay-awake
+```
+
+[show file extensions]: https://www.howtogeek.com/205086/beginner-how-to-make-windows-show-file-extensions/
+
+Then just double-click on that file.
+
+You could also edit (a copy of) `scrcpy-console.bat` or `scrcpy-noconsole.vbs`
+to add some arguments.

install_release.sh

@@ -2,8 +2,8 @@
 set -e
 
 BUILDDIR=build-auto
-PREBUILT_SERVER_URL=https://github.com/Genymobile/scrcpy/releases/download/v1.25/scrcpy-server-v1.25
-PREBUILT_SERVER_SHA256=ce0306c7bbd06ae72f6d06f7ec0ee33774995a65de71e0a83813ecb67aec9bdb
+PREBUILT_SERVER_URL=https://github.com/Genymobile/scrcpy/releases/download/v2.0/scrcpy-server-v2.0
+PREBUILT_SERVER_SHA256=9e241615f578cd690bb43311000debdecf6a9c50a7082b001952f18f6f21ddc2
 
 echo "[scrcpy] Downloading prebuilt server..."
 wget "$PREBUILT_SERVER_URL" -O scrcpy-server

meson.build

@@ -1,5 +1,5 @@
 project('scrcpy', 'c',
-        version: '1.25',
+        version: '2.0',
         meson_version: '>= 0.48',
         default_options: [
             'c_std=c11',

release.mk

@@ -94,15 +94,15 @@ dist-win32: build-server build-win32
 	cp app/data/scrcpy-noconsole.vbs "$(DIST)/$(WIN32_TARGET_DIR)"
 	cp app/data/icon.png "$(DIST)/$(WIN32_TARGET_DIR)"
 	cp app/data/open_a_terminal_here.bat "$(DIST)/$(WIN32_TARGET_DIR)"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win32/bin/avutil-58.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win32/bin/avcodec-60.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win32/bin/avformat-60.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win32/bin/swresample-4.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win32/bin/zlib1.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/platform-tools-33.0.3/adb.exe "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/platform-tools-33.0.3/AdbWinApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/platform-tools-33.0.3/AdbWinUsbApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/SDL2-2.26.1/i686-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win32/bin/avutil-58.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win32/bin/avcodec-60.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win32/bin/avformat-60.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win32/bin/swresample-4.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win32/bin/zlib1.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/platform-tools-34.0.1/adb.exe "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/platform-tools-34.0.1/AdbWinApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/platform-tools-34.0.1/AdbWinUsbApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/SDL2-2.26.4/i686-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
 	cp app/prebuilt-deps/data/libusb-1.0.26/libusb-MinGW-Win32/bin/msys-usb-1.0.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
 
 dist-win64: build-server build-win64
@@ -113,15 +113,15 @@ dist-win64: build-server build-win64
 	cp app/data/scrcpy-noconsole.vbs "$(DIST)/$(WIN64_TARGET_DIR)"
 	cp app/data/icon.png "$(DIST)/$(WIN64_TARGET_DIR)"
 	cp app/data/open_a_terminal_here.bat "$(DIST)/$(WIN64_TARGET_DIR)"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win64/bin/avutil-58.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win64/bin/avcodec-60.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win64/bin/avformat-60.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win64/bin/swresample-4.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy/win64/bin/zlib1.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/platform-tools-33.0.3/adb.exe "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/platform-tools-33.0.3/AdbWinApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/platform-tools-33.0.3/AdbWinUsbApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
-	cp app/prebuilt-deps/data/SDL2-2.26.1/x86_64-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win64/bin/avutil-58.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win64/bin/avcodec-60.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win64/bin/avformat-60.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win64/bin/swresample-4.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/ffmpeg-6.0-scrcpy-2/win64/bin/zlib1.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/platform-tools-34.0.1/adb.exe "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/platform-tools-34.0.1/AdbWinApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/platform-tools-34.0.1/AdbWinUsbApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp app/prebuilt-deps/data/SDL2-2.26.4/x86_64-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
 	cp app/prebuilt-deps/data/libusb-1.0.26/libusb-MinGW-x64/bin/msys-usb-1.0.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
 
 zip-win32: dist-win32

server/build.gradle

@@ -7,8 +7,8 @@ android {
         applicationId "com.genymobile.scrcpy"
         minSdkVersion 21
         targetSdkVersion 33
-        versionCode 12500
-        versionName "1.25"
+        versionCode 20000
+        versionName "2.0"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
     buildTypes {

server/build_without_gradle.sh

@@ -12,7 +12,7 @@
 set -e
 
 SCRCPY_DEBUG=false
-SCRCPY_VERSION_NAME=1.25
+SCRCPY_VERSION_NAME=2.0
 
 PLATFORM=${ANDROID_PLATFORM:-33}
 BUILD_TOOLS=${ANDROID_BUILD_TOOLS:-33.0.0}

server/src/main/java/com/genymobile/scrcpy/AsyncProcessor.java

@@ -0,0 +1,7 @@
+package com.genymobile.scrcpy;
+
+public interface AsyncProcessor {
+    void start();
+    void stop();
+    void join() throws InterruptedException;
+}

server/src/main/java/com/genymobile/scrcpy/AudioCapture.java

@@ -0,0 +1,147 @@
+package com.genymobile.scrcpy;
+
+import com.genymobile.scrcpy.wrappers.ServiceManager;
+
+import android.annotation.SuppressLint;
+import android.annotation.TargetApi;
+import android.content.ComponentName;
+import android.content.Intent;
+import android.media.AudioFormat;
+import android.media.AudioRecord;
+import android.media.AudioTimestamp;
+import android.media.MediaCodec;
+import android.media.MediaRecorder;
+import android.os.Build;
+import android.os.SystemClock;
+
+import java.nio.ByteBuffer;
+
+public final class AudioCapture {
+
+    public static final int SAMPLE_RATE = 48000;
+    public static final int CHANNEL_CONFIG = AudioFormat.CHANNEL_IN_STEREO;
+    public static final int CHANNELS = 2;
+    public static final int FORMAT = AudioFormat.ENCODING_PCM_16BIT;
+    public static final int BYTES_PER_SAMPLE = 2;
+
+    private AudioRecord recorder;
+
+    private final AudioTimestamp timestamp = new AudioTimestamp();
+    private long previousPts = 0;
+    private long nextPts = 0;
+
+    public static int millisToBytes(int millis) {
+        return SAMPLE_RATE * CHANNELS * BYTES_PER_SAMPLE * millis / 1000;
+    }
+
+    private static AudioFormat createAudioFormat() {
+        AudioFormat.Builder builder = new AudioFormat.Builder();
+        builder.setEncoding(FORMAT);
+        builder.setSampleRate(SAMPLE_RATE);
+        builder.setChannelMask(CHANNEL_CONFIG);
+        return builder.build();
+    }
+
+    @TargetApi(Build.VERSION_CODES.M)
+    @SuppressLint({"WrongConstant", "MissingPermission"})
+    private static AudioRecord createAudioRecord() {
+        AudioRecord.Builder builder = new AudioRecord.Builder();
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+            // On older APIs, Workarounds.fillAppInfo() must be called beforehand
+            builder.setContext(FakeContext.get());
+        }
+        builder.setAudioSource(MediaRecorder.AudioSource.REMOTE_SUBMIX);
+        builder.setAudioFormat(createAudioFormat());
+        int minBufferSize = AudioRecord.getMinBufferSize(SAMPLE_RATE, CHANNEL_CONFIG, FORMAT);
+        // This buffer size does not impact latency
+        builder.setBufferSizeInBytes(8 * minBufferSize);
+        return builder.build();
+    }
+
+    private static void startWorkaroundAndroid11() {
+        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
+            // Android 11 requires Apps to be at foreground to record audio.
+            // Normally, each App has its own user ID, so Android checks whether the requesting App has the user ID that's at the foreground.
+            // But scrcpy server is NOT an App, it's a Java application started from Android shell, so it has the same user ID (2000) with Android
+            // shell ("com.android.shell").
+            // If there is an Activity from Android shell running at foreground, then the permission system will believe scrcpy is also in the
+            // foreground.
+            if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
+                Intent intent = new Intent(Intent.ACTION_MAIN);
+                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                intent.addCategory(Intent.CATEGORY_LAUNCHER);
+                intent.setComponent(new ComponentName(FakeContext.PACKAGE_NAME, "com.android.shell.HeapDumpActivity"));
+                ServiceManager.getActivityManager().startActivityAsUserWithFeature(intent);
+                // Wait for activity to start
+                SystemClock.sleep(150);
+            }
+        }
+    }
+
+    private static void stopWorkaroundAndroid11() {
+        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
+            ServiceManager.getActivityManager().forceStopPackage(FakeContext.PACKAGE_NAME);
+        }
+    }
+
+    public void start() throws AudioCaptureForegroundException {
+        startWorkaroundAndroid11();
+        try {
+            recorder = createAudioRecord();
+            recorder.startRecording();
+        } catch (UnsupportedOperationException e) {
+            if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
+                Ln.e("Failed to start audio capture");
+                Ln.e("On Android 11, it is only possible to capture in foreground, make sure that the device is unlocked when starting scrcpy.");
+                throw new AudioCaptureForegroundException();
+            }
+            throw e;
+        } finally {
+            stopWorkaroundAndroid11();
+        }
+    }
+
+    public void stop() {
+        if (recorder != null) {
+            // Will call .stop() if necessary, without throwing an IllegalStateException
+            recorder.release();
+        }
+    }
+
+    @TargetApi(Build.VERSION_CODES.N)
+    public int read(ByteBuffer directBuffer, int size, MediaCodec.BufferInfo outBufferInfo) {
+        int r = recorder.read(directBuffer, size);
+        if (r <= 0) {
+            return r;
+        }
+
+        long pts;
+
+        int ret = recorder.getTimestamp(timestamp, AudioTimestamp.TIMEBASE_MONOTONIC);
+        if (ret == AudioRecord.SUCCESS) {
+            pts = timestamp.nanoTime / 1000;
+        } else {
+            if (nextPts == 0) {
+                Ln.w("Could not get any audio timestamp");
+            }
+            // compute from previous timestamp and packet size
+            pts = nextPts;
+        }
+
+        long durationUs = r * 1000000 / (CHANNELS * BYTES_PER_SAMPLE * SAMPLE_RATE);
+        nextPts = pts + durationUs;
+
+        if (previousPts != 0 && pts < previousPts) {
+            // Audio PTS may come from two sources:
+            //  - recorder.getTimestamp() if the call works;
+            //  - an estimation from the previous PTS and the packet size as a fallback.
+            //
+            // Therefore, the property that PTS are monotonically increasing is no guaranteed in corner cases, so enforce it.
+            pts = previousPts + 1;
+        }
+        previousPts = pts;
+
+        outBufferInfo.set(0, r, pts, 0);
+        return r;
+    }
+}

server/src/main/java/com/genymobile/scrcpy/AudioCaptureForegroundException.java

@@ -0,0 +1,7 @@
+package com.genymobile.scrcpy;
+
+/**
+ * Exception thrown if audio capture failed on Android 11 specifically because the running App (shell) was not in foreground.
+ */
+public class AudioCaptureForegroundException extends Exception {
+}

server/src/main/java/com/genymobile/scrcpy/AudioCodec.java

@@ -4,7 +4,8 @@ import android.media.MediaFormat;
 
 public enum AudioCodec implements Codec {
     OPUS(0x6f_70_75_73, "opus", MediaFormat.MIMETYPE_AUDIO_OPUS),
-    AAC(0x00_61_61_63, "aac", MediaFormat.MIMETYPE_AUDIO_AAC);
+    AAC(0x00_61_61_63, "aac", MediaFormat.MIMETYPE_AUDIO_AAC),
+    RAW(0x00_72_61_77, "raw", MediaFormat.MIMETYPE_AUDIO_RAW);
 
     private final int id; // 4-byte ASCII representation of the name
     private final String name;

server/src/main/java/com/genymobile/scrcpy/AudioEncoder.java

@@ -1,22 +1,12 @@
 package com.genymobile.scrcpy;
 
-import com.genymobile.scrcpy.wrappers.ServiceManager;
-
-import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
-import android.content.ComponentName;
-import android.content.Intent;
-import android.media.AudioFormat;
-import android.media.AudioRecord;
-import android.media.AudioTimestamp;
 import android.media.MediaCodec;
 import android.media.MediaFormat;
-import android.media.MediaRecorder;
 import android.os.Build;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.Looper;
-import android.os.SystemClock;
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
@@ -24,7 +14,7 @@ import java.util.List;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 
-public final class AudioEncoder {
+public final class AudioEncoder implements AsyncProcessor {
 
     private static class InputTask {
         private final int index;
@@ -44,14 +34,11 @@ public final class AudioEncoder {
         }
     }
 
-    private static final int SAMPLE_RATE = 48000;
-    private static final int CHANNEL_CONFIG = AudioFormat.CHANNEL_IN_STEREO;
-    private static final int CHANNELS = 2;
-    private static final int FORMAT = AudioFormat.ENCODING_PCM_16BIT;
-    private static final int BYTES_PER_SAMPLE = 2;
+    private static final int SAMPLE_RATE = AudioCapture.SAMPLE_RATE;
+    private static final int CHANNELS = AudioCapture.CHANNELS;
 
-    private static final int BUFFER_MS = 5; // milliseconds
-    private static final int BUFFER_SIZE = SAMPLE_RATE * CHANNELS * BYTES_PER_SAMPLE * BUFFER_MS / 1000;
+    private static final int READ_MS = 5; // milliseconds
+    private static final int READ_SIZE = AudioCapture.millisToBytes(READ_MS);
 
     private final Streamer streamer;
     private final int bitRate;
@@ -78,29 +65,6 @@ public final class AudioEncoder {
         this.encoderName = encoderName;
     }
 
-    private static AudioFormat createAudioFormat() {
-        AudioFormat.Builder builder = new AudioFormat.Builder();
-        builder.setEncoding(FORMAT);
-        builder.setSampleRate(SAMPLE_RATE);
-        builder.setChannelMask(CHANNEL_CONFIG);
-        return builder.build();
-    }
-
-    @TargetApi(Build.VERSION_CODES.M)
-    @SuppressLint({"WrongConstant", "MissingPermission"})
-    private static AudioRecord createAudioRecord() {
-        AudioRecord.Builder builder = new AudioRecord.Builder();
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
-            // On older APIs, Workarounds.fillAppInfo() must be called beforehand
-            builder.setContext(FakeContext.get());
-        }
-        builder.setAudioSource(MediaRecorder.AudioSource.REMOTE_SUBMIX);
-        builder.setAudioFormat(createAudioFormat());
-        int minBufferSize = AudioRecord.getMinBufferSize(SAMPLE_RATE, CHANNEL_CONFIG, FORMAT);
-        builder.setBufferSizeInBytes(minBufferSize);
-        return builder.build();
-    }
-
     private static MediaFormat createFormat(String mimeType, int bitRate, List<CodecOption> codecOptions) {
         MediaFormat format = new MediaFormat();
         format.setString(MediaFormat.KEY_MIME, mimeType);
@@ -121,52 +85,23 @@ public final class AudioEncoder {
     }
 
     @TargetApi(Build.VERSION_CODES.N)
-    private void inputThread(MediaCodec mediaCodec, AudioRecord recorder) throws IOException, InterruptedException {
-        final AudioTimestamp timestamp = new AudioTimestamp();
-        long previousPts = 0;
-        long nextPts = 0;
+    private void inputThread(MediaCodec mediaCodec, AudioCapture capture) throws IOException, InterruptedException {
+        final MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
 
         while (!Thread.currentThread().isInterrupted()) {
             InputTask task = inputTasks.take();
             ByteBuffer buffer = mediaCodec.getInputBuffer(task.index);
-            int r = recorder.read(buffer, BUFFER_SIZE);
-            if (r < 0) {
+            int r = capture.read(buffer, READ_SIZE, bufferInfo);
+            if (r <= 0) {
                 throw new IOException("Could not read audio: " + r);
             }
 
-            long pts;
-
-            int ret = recorder.getTimestamp(timestamp, AudioTimestamp.TIMEBASE_MONOTONIC);
-            if (ret == AudioRecord.SUCCESS) {
-                pts = timestamp.nanoTime / 1000;
-            } else {
-                if (nextPts == 0) {
-                    Ln.w("Could not get any audio timestamp");
-                }
-                // compute from previous timestamp and packet size
-                pts = nextPts;
-            }
-
-            long durationMs = r * 1000 / CHANNELS / SAMPLE_RATE;
-            nextPts = pts + durationMs;
-
-            if (previousPts != 0 && pts < previousPts) {
-                // Audio PTS may come from two sources:
-                //  - recorder.getTimestamp() if the call works;
-                //  - an estimation from the previous PTS and the packet size as a fallback.
-                //
-                // Therefore, the property that PTS are monotonically increasing is no guaranteed in corner cases, so enforce it.
-                pts = previousPts + 1;
-            }
-
-            mediaCodec.queueInputBuffer(task.index, 0, r, pts, 0);
-
-            previousPts = pts;
+            mediaCodec.queueInputBuffer(task.index, bufferInfo.offset, bufferInfo.size, bufferInfo.presentationTimeUs, bufferInfo.flags);
         }
     }
 
     private void outputThread(MediaCodec mediaCodec) throws IOException, InterruptedException {
-        streamer.writeHeader();
+        streamer.writeAudioHeader();
 
         while (!Thread.currentThread().isInterrupted()) {
             OutputTask task = outputTasks.take();
@@ -183,6 +118,8 @@ public final class AudioEncoder {
         thread = new Thread(() -> {
             try {
                 encode();
+            } catch (ConfigurationException | AudioCaptureForegroundException e) {
+                // Do not print stack trace, a user-friendly error-message has already been logged
             } catch (IOException e) {
                 Ln.e("Audio encoding error", e);
             } finally {
@@ -220,34 +157,8 @@ public final class AudioEncoder {
         }
     }
 
-    private static void startWorkaroundAndroid11() {
-        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
-            // Android 11 requires Apps to be at foreground to record audio.
-            // Normally, each App has its own user ID, so Android checks whether the requesting App has the user ID that's at the foreground.
-            // But Scrcpy server is NOT an App, it's a Java application started from Android shell, so it has the same user ID (2000) with Android
-            // shell ("com.android.shell").
-            // If there is an Activity from Android shell running at foreground, then the permission system will believe Scrcpy is also in the
-            // foreground.
-            if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
-                Intent intent = new Intent(Intent.ACTION_MAIN);
-                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-                intent.addCategory(Intent.CATEGORY_LAUNCHER);
-                intent.setComponent(new ComponentName(FakeContext.PACKAGE_NAME, "com.android.shell.HeapDumpActivity"));
-                ServiceManager.getActivityManager().startActivityAsUserWithFeature(intent);
-                // Wait for activity to start
-                SystemClock.sleep(150);
-            }
-        }
-    }
-
-    private static void stopWorkaroundAndroid11() {
-        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
-            ServiceManager.getActivityManager().forceStopPackage(FakeContext.PACKAGE_NAME);
-        }
-    }
-
     @TargetApi(Build.VERSION_CODES.M)
-    public void encode() throws IOException {
+    public void encode() throws IOException, ConfigurationException, AudioCaptureForegroundException {
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.R) {
             Ln.w("Audio disabled: it is not supported before Android 11");
             streamer.writeDisableStream(false);
@@ -255,11 +166,9 @@ public final class AudioEncoder {
         }
 
         MediaCodec mediaCodec = null;
-        AudioRecord recorder = null;
+        AudioCapture capture = new AudioCapture();
 
         boolean mediaCodecStarted = false;
-        boolean recorderStarted = false;
-        boolean configurationError = false;
         try {
             Codec codec = streamer.getCodec();
             mediaCodec = createMediaCodec(codec, encoderName);
@@ -271,26 +180,13 @@ public final class AudioEncoder {
             mediaCodec.setCallback(new EncoderCallback(), new Handler(mediaCodecThread.getLooper()));
             mediaCodec.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
 
-            startWorkaroundAndroid11();
-            try {
-                recorder = createAudioRecord();
-                recorder.startRecording();
-            } catch (UnsupportedOperationException e) {
-                if (Build.VERSION.SDK_INT == Build.VERSION_CODES.R) {
-                    Ln.e("Failed to start audio capture");
-                    Ln.e("On Android 11, it is only possible to capture in foreground, make sure that the device is unlocked when starting scrcpy.");
-                    throw new ConfigurationException("Unsupported audio capture");
-                }
-            } finally {
-                stopWorkaroundAndroid11();
-            }
-            recorderStarted = true;
+            capture.start();
 
             final MediaCodec mediaCodecRef = mediaCodec;
-            final AudioRecord recorderRef = recorder;
+            final AudioCapture captureRef = capture;
             inputThread = new Thread(() -> {
                 try {
-                    inputThread(mediaCodecRef, recorderRef);
+                    inputThread(mediaCodecRef, captureRef);
                 } catch (IOException | InterruptedException e) {
                     Ln.e("Audio capture error", e);
                 } finally {
@@ -320,15 +216,14 @@ public final class AudioEncoder {
 
             waitEnded();
         } catch (ConfigurationException e) {
-            // Do not print stack trace, a user-friendly error-message has already been logged
-            // Notify the error to scrcpy to make it exit
-            configurationError = true;
+            // Notify the error to make scrcpy exit
+            streamer.writeDisableStream(true);
+            throw e;
+        } catch (Throwable e) {
+            // Notify the client that the audio could not be captured
+            streamer.writeDisableStream(false);
+            throw e;
         } finally {
-            if (!recorderStarted) {
-                // Notify the client that the audio could not be captured
-                streamer.writeDisableStream(configurationError);
-            }
-
             // Cleanup everything (either at the end or on error at any step of the initialization)
             if (mediaCodecThread != null) {
                 Looper looper = mediaCodecThread.getLooper();
@@ -364,11 +259,8 @@ public final class AudioEncoder {
                 }
                 mediaCodec.release();
             }
-            if (recorder != null) {
-                if (recorderStarted) {
-                    recorder.stop();
-                }
-                recorder.release();
+            if (capture != null) {
+                capture.stop();
             }
         }
     }

server/src/main/java/com/genymobile/scrcpy/AudioRawRecorder.java

@@ -0,0 +1,75 @@
+package com.genymobile.scrcpy;
+
+import android.media.MediaCodec;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+public final class AudioRawRecorder implements AsyncProcessor {
+
+    private final Streamer streamer;
+
+    private Thread thread;
+
+    private static final int READ_MS = 5; // milliseconds
+    private static final int READ_SIZE = AudioCapture.millisToBytes(READ_MS);
+
+    public AudioRawRecorder(Streamer streamer) {
+        this.streamer = streamer;
+    }
+
+    private void record() throws IOException, AudioCaptureForegroundException {
+        final ByteBuffer buffer = ByteBuffer.allocateDirect(READ_SIZE);
+        final MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
+
+        AudioCapture capture = new AudioCapture();
+        try {
+            capture.start();
+
+            streamer.writeAudioHeader();
+            while (!Thread.currentThread().isInterrupted()) {
+                buffer.position(0);
+                int r = capture.read(buffer, READ_SIZE, bufferInfo);
+                if (r < 0) {
+                    throw new IOException("Could not read audio: " + r);
+                }
+                buffer.limit(r);
+
+                streamer.writePacket(buffer, bufferInfo);
+            }
+        } catch (Throwable e) {
+            // Notify the client that the audio could not be captured
+            streamer.writeDisableStream(false);
+            throw e;
+        } finally {
+            capture.stop();
+        }
+    }
+
+    public void start() {
+        thread = new Thread(() -> {
+            try {
+                record();
+            } catch (AudioCaptureForegroundException e) {
+                // Do not print stack trace, a user-friendly error-message has already been logged
+            } catch (IOException e) {
+                Ln.e("Audio recording error", e);
+            } finally {
+                Ln.d("Audio recorder stopped");
+            }
+        });
+        thread.start();
+    }
+
+    public void stop() {
+        if (thread != null) {
+            thread.interrupt();
+        }
+    }
+
+    public void join() throws InterruptedException {
+        if (thread != null) {
+            thread.join();
+        }
+    }
+}

server/src/main/java/com/genymobile/scrcpy/Controller.java

@@ -14,7 +14,7 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 
-public class Controller {
+public class Controller implements AsyncProcessor {
 
     private static final int DEFAULT_DEVICE_ID = 0;