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android_frameworks_base/tools/aapt/Images.cpp
Adam Lesinski e572c011fe AAPT: Continuation of public/private attribute fix 
XML files like layouts are now scanned and checked
for v21 attributes. If those kinds of attributes
are found, then we remove them in the original
version and synthesize a new xml file under the
v21 configuration.

Bug:17520380
Change-Id: Icf984cb96134180a2e35349c1dbf2cef9a8f0bda
2014-09-22 10:51:20 -07:00

1500 lines
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//
// Copyright 2006 The Android Open Source Project
//
// Build resource files from raw assets.
//
#define PNG_INTERNAL
#include "Images.h"
#include <androidfw/ResourceTypes.h>
#include <utils/ByteOrder.h>
#include <png.h>
#include <zlib.h>
#define NOISY(x) //x
static void
png_write_aapt_file(png_structp png_ptr, png_bytep data, png_size_t length)
{
AaptFile* aaptfile = (AaptFile*) png_get_io_ptr(png_ptr);
status_t err = aaptfile->writeData(data, length);
if (err != NO_ERROR) {
png_error(png_ptr, "Write Error");
}
}
static void
png_flush_aapt_file(png_structp png_ptr)
{
}
// This holds an image as 8bpp RGBA.
struct image_info
{
image_info() : rows(NULL), is9Patch(false),
xDivs(NULL), yDivs(NULL), colors(NULL), allocRows(NULL) { }
~image_info() {
if (rows && rows != allocRows) {
free(rows);
}
if (allocRows) {
for (int i=0; i<(int)allocHeight; i++) {
free(allocRows[i]);
}
free(allocRows);
}
free(xDivs);
free(yDivs);
free(colors);
}
void* serialize9patch() {
void* serialized = Res_png_9patch::serialize(info9Patch, xDivs, yDivs, colors);
reinterpret_cast<Res_png_9patch*>(serialized)->deviceToFile();
return serialized;
}
png_uint_32 width;
png_uint_32 height;
png_bytepp rows;
// 9-patch info.
bool is9Patch;
Res_png_9patch info9Patch;
int32_t* xDivs;
int32_t* yDivs;
uint32_t* colors;
// Layout padding, if relevant
bool haveLayoutBounds;
int32_t layoutBoundsLeft;
int32_t layoutBoundsTop;
int32_t layoutBoundsRight;
int32_t layoutBoundsBottom;
// Round rect outline description
int32_t outlineInsetsLeft;
int32_t outlineInsetsTop;
int32_t outlineInsetsRight;
int32_t outlineInsetsBottom;
float outlineRadius;
uint8_t outlineAlpha;
png_uint_32 allocHeight;
png_bytepp allocRows;
};
static void log_warning(png_structp png_ptr, png_const_charp warning_message)
{
const char* imageName = (const char*) png_get_error_ptr(png_ptr);
fprintf(stderr, "%s: libpng warning: %s\n", imageName, warning_message);
}
static void read_png(const char* imageName,
png_structp read_ptr, png_infop read_info,
image_info* outImageInfo)
{
int color_type;
int bit_depth, interlace_type, compression_type;
int i;
png_set_error_fn(read_ptr, const_cast<char*>(imageName),
NULL /* use default errorfn */, log_warning);
png_read_info(read_ptr, read_info);
png_get_IHDR(read_ptr, read_info, &outImageInfo->width,
&outImageInfo->height, &bit_depth, &color_type,
&interlace_type, &compression_type, NULL);
//printf("Image %s:\n", imageName);
//printf("color_type=%d, bit_depth=%d, interlace_type=%d, compression_type=%d\n",
// color_type, bit_depth, interlace_type, compression_type);
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(read_ptr);
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand_gray_1_2_4_to_8(read_ptr);
if (png_get_valid(read_ptr, read_info, PNG_INFO_tRNS)) {
//printf("Has PNG_INFO_tRNS!\n");
png_set_tRNS_to_alpha(read_ptr);
}
if (bit_depth == 16)
png_set_strip_16(read_ptr);
if ((color_type&PNG_COLOR_MASK_ALPHA) == 0)
png_set_add_alpha(read_ptr, 0xFF, PNG_FILLER_AFTER);
if (color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(read_ptr);
png_set_interlace_handling(read_ptr);
png_read_update_info(read_ptr, read_info);
outImageInfo->rows = (png_bytepp)malloc(
outImageInfo->height * sizeof(png_bytep));
outImageInfo->allocHeight = outImageInfo->height;
outImageInfo->allocRows = outImageInfo->rows;
png_set_rows(read_ptr, read_info, outImageInfo->rows);
for (i = 0; i < (int)outImageInfo->height; i++)
{
outImageInfo->rows[i] = (png_bytep)
malloc(png_get_rowbytes(read_ptr, read_info));
}
png_read_image(read_ptr, outImageInfo->rows);
png_read_end(read_ptr, read_info);
NOISY(printf("Image %s: w=%d, h=%d, d=%d, colors=%d, inter=%d, comp=%d\n",
imageName,
(int)outImageInfo->width, (int)outImageInfo->height,
bit_depth, color_type,
interlace_type, compression_type));
png_get_IHDR(read_ptr, read_info, &outImageInfo->width,
&outImageInfo->height, &bit_depth, &color_type,
&interlace_type, &compression_type, NULL);
}
#define COLOR_TRANSPARENT 0
#define COLOR_WHITE 0xFFFFFFFF
#define COLOR_TICK 0xFF000000
#define COLOR_LAYOUT_BOUNDS_TICK 0xFF0000FF
enum {
TICK_TYPE_NONE,
TICK_TYPE_TICK,
TICK_TYPE_LAYOUT_BOUNDS,
TICK_TYPE_BOTH
};
static int tick_type(png_bytep p, bool transparent, const char** outError)
{
png_uint_32 color = p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
if (transparent) {
if (p[3] == 0) {
return TICK_TYPE_NONE;
}
if (color == COLOR_LAYOUT_BOUNDS_TICK) {
return TICK_TYPE_LAYOUT_BOUNDS;
}
if (color == COLOR_TICK) {
return TICK_TYPE_TICK;
}
// Error cases
if (p[3] != 0xff) {
*outError = "Frame pixels must be either solid or transparent (not intermediate alphas)";
return TICK_TYPE_NONE;
}
if (p[0] != 0 || p[1] != 0 || p[2] != 0) {
*outError = "Ticks in transparent frame must be black or red";
}
return TICK_TYPE_TICK;
}
if (p[3] != 0xFF) {
*outError = "White frame must be a solid color (no alpha)";
}
if (color == COLOR_WHITE) {
return TICK_TYPE_NONE;
}
if (color == COLOR_TICK) {
return TICK_TYPE_TICK;
}
if (color == COLOR_LAYOUT_BOUNDS_TICK) {
return TICK_TYPE_LAYOUT_BOUNDS;
}
if (p[0] != 0 || p[1] != 0 || p[2] != 0) {
*outError = "Ticks in white frame must be black or red";
return TICK_TYPE_NONE;
}
return TICK_TYPE_TICK;
}
enum {
TICK_START,
TICK_INSIDE_1,
TICK_OUTSIDE_1
};
static status_t get_horizontal_ticks(
png_bytep row, int width, bool transparent, bool required,
int32_t* outLeft, int32_t* outRight, const char** outError,
uint8_t* outDivs, bool multipleAllowed)
{
int i;
*outLeft = *outRight = -1;
int state = TICK_START;
bool found = false;
for (i=1; i<width-1; i++) {
if (TICK_TYPE_TICK == tick_type(row+i*4, transparent, outError)) {
if (state == TICK_START ||
(state == TICK_OUTSIDE_1 && multipleAllowed)) {
*outLeft = i-1;
*outRight = width-2;
found = true;
if (outDivs != NULL) {
*outDivs += 2;
}
state = TICK_INSIDE_1;
} else if (state == TICK_OUTSIDE_1) {
*outError = "Can't have more than one marked region along edge";
*outLeft = i;
return UNKNOWN_ERROR;
}
} else if (*outError == NULL) {
if (state == TICK_INSIDE_1) {
// We're done with this div. Move on to the next.
*outRight = i-1;
outRight += 2;
outLeft += 2;
state = TICK_OUTSIDE_1;
}
} else {
*outLeft = i;
return UNKNOWN_ERROR;
}
}
if (required && !found) {
*outError = "No marked region found along edge";
*outLeft = -1;
return UNKNOWN_ERROR;
}
return NO_ERROR;
}
static status_t get_vertical_ticks(
png_bytepp rows, int offset, int height, bool transparent, bool required,
int32_t* outTop, int32_t* outBottom, const char** outError,
uint8_t* outDivs, bool multipleAllowed)
{
int i;
*outTop = *outBottom = -1;
int state = TICK_START;
bool found = false;
for (i=1; i<height-1; i++) {
if (TICK_TYPE_TICK == tick_type(rows[i]+offset, transparent, outError)) {
if (state == TICK_START ||
(state == TICK_OUTSIDE_1 && multipleAllowed)) {
*outTop = i-1;
*outBottom = height-2;
found = true;
if (outDivs != NULL) {
*outDivs += 2;
}
state = TICK_INSIDE_1;
} else if (state == TICK_OUTSIDE_1) {
*outError = "Can't have more than one marked region along edge";
*outTop = i;
return UNKNOWN_ERROR;
}
} else if (*outError == NULL) {
if (state == TICK_INSIDE_1) {
// We're done with this div. Move on to the next.
*outBottom = i-1;
outTop += 2;
outBottom += 2;
state = TICK_OUTSIDE_1;
}
} else {
*outTop = i;
return UNKNOWN_ERROR;
}
}
if (required && !found) {
*outError = "No marked region found along edge";
*outTop = -1;
return UNKNOWN_ERROR;
}
return NO_ERROR;
}
static status_t get_horizontal_layout_bounds_ticks(
png_bytep row, int width, bool transparent, bool required,
int32_t* outLeft, int32_t* outRight, const char** outError)
{
int i;
*outLeft = *outRight = 0;
// Look for left tick
if (TICK_TYPE_LAYOUT_BOUNDS == tick_type(row + 4, transparent, outError)) {
// Starting with a layout padding tick
i = 1;
while (i < width - 1) {
(*outLeft)++;
i++;
int tick = tick_type(row + i * 4, transparent, outError);
if (tick != TICK_TYPE_LAYOUT_BOUNDS) {
break;
}
}
}
// Look for right tick
if (TICK_TYPE_LAYOUT_BOUNDS == tick_type(row + (width - 2) * 4, transparent, outError)) {
// Ending with a layout padding tick
i = width - 2;
while (i > 1) {
(*outRight)++;
i--;
int tick = tick_type(row+i*4, transparent, outError);
if (tick != TICK_TYPE_LAYOUT_BOUNDS) {
break;
}
}
}
return NO_ERROR;
}
static status_t get_vertical_layout_bounds_ticks(
png_bytepp rows, int offset, int height, bool transparent, bool required,
int32_t* outTop, int32_t* outBottom, const char** outError)
{
int i;
*outTop = *outBottom = 0;
// Look for top tick
if (TICK_TYPE_LAYOUT_BOUNDS == tick_type(rows[1] + offset, transparent, outError)) {
// Starting with a layout padding tick
i = 1;
while (i < height - 1) {
(*outTop)++;
i++;
int tick = tick_type(rows[i] + offset, transparent, outError);
if (tick != TICK_TYPE_LAYOUT_BOUNDS) {
break;
}
}
}
// Look for bottom tick
if (TICK_TYPE_LAYOUT_BOUNDS == tick_type(rows[height - 2] + offset, transparent, outError)) {
// Ending with a layout padding tick
i = height - 2;
while (i > 1) {
(*outBottom)++;
i--;
int tick = tick_type(rows[i] + offset, transparent, outError);
if (tick != TICK_TYPE_LAYOUT_BOUNDS) {
break;
}
}
}
return NO_ERROR;
}
static void find_max_opacity(png_byte** rows,
int startX, int startY, int endX, int endY, int dX, int dY,
int* out_inset)
{
bool opaque_within_inset = true;
uint8_t max_opacity = 0;
int inset = 0;
*out_inset = 0;
for (int x = startX, y = startY; x != endX && y != endY; x += dX, y += dY, inset++) {
png_byte* color = rows[y] + x * 4;
uint8_t opacity = color[3];
if (opacity > max_opacity) {
max_opacity = opacity;
*out_inset = inset;
}
if (opacity == 0xff) return;
}
}
static uint8_t max_alpha_over_row(png_byte* row, int startX, int endX)
{
uint8_t max_alpha = 0;
for (int x = startX; x < endX; x++) {
uint8_t alpha = (row + x * 4)[3];
if (alpha > max_alpha) max_alpha = alpha;
}
return max_alpha;
}
static uint8_t max_alpha_over_col(png_byte** rows, int offsetX, int startY, int endY)
{
uint8_t max_alpha = 0;
for (int y = startY; y < endY; y++) {
uint8_t alpha = (rows[y] + offsetX * 4)[3];
if (alpha > max_alpha) max_alpha = alpha;
}
return max_alpha;
}
static void get_outline(image_info* image)
{
int midX = image->width / 2;
int midY = image->height / 2;
int endX = image->width - 2;
int endY = image->height - 2;
// find left and right extent of nine patch content on center row
if (image->width > 4) {
find_max_opacity(image->rows, 1, midY, midX, -1, 1, 0, &image->outlineInsetsLeft);
find_max_opacity(image->rows, endX, midY, midX, -1, -1, 0, &image->outlineInsetsRight);
} else {
image->outlineInsetsLeft = 0;
image->outlineInsetsRight = 0;
}
// find top and bottom extent of nine patch content on center column
if (image->height > 4) {
find_max_opacity(image->rows, midX, 1, -1, midY, 0, 1, &image->outlineInsetsTop);
find_max_opacity(image->rows, midX, endY, -1, midY, 0, -1, &image->outlineInsetsBottom);
} else {
image->outlineInsetsTop = 0;
image->outlineInsetsBottom = 0;
}
int innerStartX = 1 + image->outlineInsetsLeft;
int innerStartY = 1 + image->outlineInsetsTop;
int innerEndX = endX - image->outlineInsetsRight;
int innerEndY = endY - image->outlineInsetsBottom;
int innerMidX = (innerEndX + innerStartX) / 2;
int innerMidY = (innerEndY + innerStartY) / 2;
// assuming the image is a round rect, compute the radius by marching
// diagonally from the top left corner towards the center
image->outlineAlpha = max(max_alpha_over_row(image->rows[innerMidY], innerStartX, innerEndX),
max_alpha_over_col(image->rows, innerMidX, innerStartY, innerStartY));
int diagonalInset = 0;
find_max_opacity(image->rows, innerStartX, innerStartY, innerMidX, innerMidY, 1, 1,
&diagonalInset);
/* Determine source radius based upon inset:
* sqrt(r^2 + r^2) = sqrt(i^2 + i^2) + r
* sqrt(2) * r = sqrt(2) * i + r
* (sqrt(2) - 1) * r = sqrt(2) * i
* r = sqrt(2) / (sqrt(2) - 1) * i
*/
image->outlineRadius = 3.4142f * diagonalInset;
NOISY(printf("outline insets %d %d %d %d, rad %f, alpha %x\n",
image->outlineInsetsLeft,
image->outlineInsetsTop,
image->outlineInsetsRight,
image->outlineInsetsBottom,
image->outlineRadius,
image->outlineAlpha));
}
static uint32_t get_color(
png_bytepp rows, int left, int top, int right, int bottom)
{
png_bytep color = rows[top] + left*4;
if (left > right || top > bottom) {
return Res_png_9patch::TRANSPARENT_COLOR;
}
while (top <= bottom) {
for (int i = left; i <= right; i++) {
png_bytep p = rows[top]+i*4;
if (color[3] == 0) {
if (p[3] != 0) {
return Res_png_9patch::NO_COLOR;
}
} else if (p[0] != color[0] || p[1] != color[1]
|| p[2] != color[2] || p[3] != color[3]) {
return Res_png_9patch::NO_COLOR;
}
}
top++;
}
if (color[3] == 0) {
return Res_png_9patch::TRANSPARENT_COLOR;
}
return (color[3]<<24) | (color[0]<<16) | (color[1]<<8) | color[2];
}
static void select_patch(
int which, int front, int back, int size, int* start, int* end)
{
switch (which) {
case 0:
*start = 0;
*end = front-1;
break;
case 1:
*start = front;
*end = back-1;
break;
case 2:
*start = back;
*end = size-1;
break;
}
}
static uint32_t get_color(image_info* image, int hpatch, int vpatch)
{
int left, right, top, bottom;
select_patch(
hpatch, image->xDivs[0], image->xDivs[1],
image->width, &left, &right);
select_patch(
vpatch, image->yDivs[0], image->yDivs[1],
image->height, &top, &bottom);
//printf("Selecting h=%d v=%d: (%d,%d)-(%d,%d)\n",
// hpatch, vpatch, left, top, right, bottom);
const uint32_t c = get_color(image->rows, left, top, right, bottom);
NOISY(printf("Color in (%d,%d)-(%d,%d): #%08x\n", left, top, right, bottom, c));
return c;
}
static status_t do_9patch(const char* imageName, image_info* image)
{
image->is9Patch = true;
int W = image->width;
int H = image->height;
int i, j;
int maxSizeXDivs = W * sizeof(int32_t);
int maxSizeYDivs = H * sizeof(int32_t);
int32_t* xDivs = image->xDivs = (int32_t*) malloc(maxSizeXDivs);
int32_t* yDivs = image->yDivs = (int32_t*) malloc(maxSizeYDivs);
uint8_t numXDivs = 0;
uint8_t numYDivs = 0;
int8_t numColors;
int numRows;
int numCols;
int top;
int left;
int right;
int bottom;
memset(xDivs, -1, maxSizeXDivs);
memset(yDivs, -1, maxSizeYDivs);
image->info9Patch.paddingLeft = image->info9Patch.paddingRight =
image->info9Patch.paddingTop = image->info9Patch.paddingBottom = -1;
image->layoutBoundsLeft = image->layoutBoundsRight =
image->layoutBoundsTop = image->layoutBoundsBottom = 0;
png_bytep p = image->rows[0];
bool transparent = p[3] == 0;
bool hasColor = false;
const char* errorMsg = NULL;
int errorPixel = -1;
const char* errorEdge = NULL;
int colorIndex = 0;
// Validate size...
if (W < 3 || H < 3) {
errorMsg = "Image must be at least 3x3 (1x1 without frame) pixels";
goto getout;
}
// Validate frame...
if (!transparent &&
(p[0] != 0xFF || p[1] != 0xFF || p[2] != 0xFF || p[3] != 0xFF)) {
errorMsg = "Must have one-pixel frame that is either transparent or white";
goto getout;
}
// Find left and right of sizing areas...
if (get_horizontal_ticks(p, W, transparent, true, &xDivs[0],
&xDivs[1], &errorMsg, &numXDivs, true) != NO_ERROR) {
errorPixel = xDivs[0];
errorEdge = "top";
goto getout;
}
// Find top and bottom of sizing areas...
if (get_vertical_ticks(image->rows, 0, H, transparent, true, &yDivs[0],
&yDivs[1], &errorMsg, &numYDivs, true) != NO_ERROR) {
errorPixel = yDivs[0];
errorEdge = "left";
goto getout;
}
// Copy patch size data into image...
image->info9Patch.numXDivs = numXDivs;
image->info9Patch.numYDivs = numYDivs;
// Find left and right of padding area...
if (get_horizontal_ticks(image->rows[H-1], W, transparent, false, &image->info9Patch.paddingLeft,
&image->info9Patch.paddingRight, &errorMsg, NULL, false) != NO_ERROR) {
errorPixel = image->info9Patch.paddingLeft;
errorEdge = "bottom";
goto getout;
}
// Find top and bottom of padding area...
if (get_vertical_ticks(image->rows, (W-1)*4, H, transparent, false, &image->info9Patch.paddingTop,
&image->info9Patch.paddingBottom, &errorMsg, NULL, false) != NO_ERROR) {
errorPixel = image->info9Patch.paddingTop;
errorEdge = "right";
goto getout;
}
// Find left and right of layout padding...
get_horizontal_layout_bounds_ticks(image->rows[H-1], W, transparent, false,
&image->layoutBoundsLeft,
&image->layoutBoundsRight, &errorMsg);
get_vertical_layout_bounds_ticks(image->rows, (W-1)*4, H, transparent, false,
&image->layoutBoundsTop,
&image->layoutBoundsBottom, &errorMsg);
image->haveLayoutBounds = image->layoutBoundsLeft != 0
|| image->layoutBoundsRight != 0
|| image->layoutBoundsTop != 0
|| image->layoutBoundsBottom != 0;
if (image->haveLayoutBounds) {
NOISY(printf("layoutBounds=%d %d %d %d\n", image->layoutBoundsLeft, image->layoutBoundsTop,
image->layoutBoundsRight, image->layoutBoundsBottom));
}
// use opacity of pixels to estimate the round rect outline
get_outline(image);
// If padding is not yet specified, take values from size.
if (image->info9Patch.paddingLeft < 0) {
image->info9Patch.paddingLeft = xDivs[0];
image->info9Patch.paddingRight = W - 2 - xDivs[1];
} else {
// Adjust value to be correct!
image->info9Patch.paddingRight = W - 2 - image->info9Patch.paddingRight;
}
if (image->info9Patch.paddingTop < 0) {
image->info9Patch.paddingTop = yDivs[0];
image->info9Patch.paddingBottom = H - 2 - yDivs[1];
} else {
// Adjust value to be correct!
image->info9Patch.paddingBottom = H - 2 - image->info9Patch.paddingBottom;
}
NOISY(printf("Size ticks for %s: x0=%d, x1=%d, y0=%d, y1=%d\n", imageName,
xDivs[0], xDivs[1],
yDivs[0], yDivs[1]));
NOISY(printf("padding ticks for %s: l=%d, r=%d, t=%d, b=%d\n", imageName,
image->info9Patch.paddingLeft, image->info9Patch.paddingRight,
image->info9Patch.paddingTop, image->info9Patch.paddingBottom));
// Remove frame from image.
image->rows = (png_bytepp)malloc((H-2) * sizeof(png_bytep));
for (i=0; i<(H-2); i++) {
image->rows[i] = image->allocRows[i+1];
memmove(image->rows[i], image->rows[i]+4, (W-2)*4);
}
image->width -= 2;
W = image->width;
image->height -= 2;
H = image->height;
// Figure out the number of rows and columns in the N-patch
numCols = numXDivs + 1;
if (xDivs[0] == 0) { // Column 1 is strechable
numCols--;
}
if (xDivs[numXDivs - 1] == W) {
numCols--;
}
numRows = numYDivs + 1;
if (yDivs[0] == 0) { // Row 1 is strechable
numRows--;
}
if (yDivs[numYDivs - 1] == H) {
numRows--;
}
// Make sure the amount of rows and columns will fit in the number of
// colors we can use in the 9-patch format.
if (numRows * numCols > 0x7F) {
errorMsg = "Too many rows and columns in 9-patch perimeter";
goto getout;
}
numColors = numRows * numCols;
image->info9Patch.numColors = numColors;
image->colors = (uint32_t*)malloc(numColors * sizeof(uint32_t));
// Fill in color information for each patch.
uint32_t c;
top = 0;
// The first row always starts with the top being at y=0 and the bottom
// being either yDivs[1] (if yDivs[0]=0) of yDivs[0]. In the former case
// the first row is stretchable along the Y axis, otherwise it is fixed.
// The last row always ends with the bottom being bitmap.height and the top
// being either yDivs[numYDivs-2] (if yDivs[numYDivs-1]=bitmap.height) or
// yDivs[numYDivs-1]. In the former case the last row is stretchable along
// the Y axis, otherwise it is fixed.
//
// The first and last columns are similarly treated with respect to the X
// axis.
//
// The above is to help explain some of the special casing that goes on the
// code below.
// The initial yDiv and whether the first row is considered stretchable or
// not depends on whether yDiv[0] was zero or not.
for (j = (yDivs[0] == 0 ? 1 : 0);
j <= numYDivs && top < H;
j++) {
if (j == numYDivs) {
bottom = H;
} else {
bottom = yDivs[j];
}
left = 0;
// The initial xDiv and whether the first column is considered
// stretchable or not depends on whether xDiv[0] was zero or not.
for (i = xDivs[0] == 0 ? 1 : 0;
i <= numXDivs && left < W;
i++) {
if (i == numXDivs) {
right = W;
} else {
right = xDivs[i];
}
c = get_color(image->rows, left, top, right - 1, bottom - 1);
image->colors[colorIndex++] = c;
NOISY(if (c != Res_png_9patch::NO_COLOR) hasColor = true);
left = right;
}
top = bottom;
}
assert(colorIndex == numColors);
for (i=0; i<numColors; i++) {
if (hasColor) {
if (i == 0) printf("Colors in %s:\n ", imageName);
printf(" #%08x", image->colors[i]);
if (i == numColors - 1) printf("\n");
}
}
getout:
if (errorMsg) {
fprintf(stderr,
"ERROR: 9-patch image %s malformed.\n"
" %s.\n", imageName, errorMsg);
if (errorEdge != NULL) {
if (errorPixel >= 0) {
fprintf(stderr,
" Found at pixel #%d along %s edge.\n", errorPixel, errorEdge);
} else {
fprintf(stderr,
" Found along %s edge.\n", errorEdge);
}
}
return UNKNOWN_ERROR;
}
return NO_ERROR;
}
static void checkNinePatchSerialization(Res_png_9patch* inPatch, void* data)
{
size_t patchSize = inPatch->serializedSize();
void* newData = malloc(patchSize);
memcpy(newData, data, patchSize);
Res_png_9patch* outPatch = inPatch->deserialize(newData);
// deserialization is done in place, so outPatch == newData
assert(outPatch == newData);
assert(outPatch->numXDivs == inPatch->numXDivs);
assert(outPatch->numYDivs == inPatch->numYDivs);
assert(outPatch->paddingLeft == inPatch->paddingLeft);
assert(outPatch->paddingRight == inPatch->paddingRight);
assert(outPatch->paddingTop == inPatch->paddingTop);
assert(outPatch->paddingBottom == inPatch->paddingBottom);
for (int i = 0; i < outPatch->numXDivs; i++) {
assert(outPatch->xDivs[i] == inPatch->xDivs[i]);
}
for (int i = 0; i < outPatch->numYDivs; i++) {
assert(outPatch->yDivs[i] == inPatch->yDivs[i]);
}
for (int i = 0; i < outPatch->numColors; i++) {
assert(outPatch->colors[i] == inPatch->colors[i]);
}
free(newData);
}
static void dump_image(int w, int h, png_bytepp rows, int color_type)
{
int i, j, rr, gg, bb, aa;
int bpp;
if (color_type == PNG_COLOR_TYPE_PALETTE || color_type == PNG_COLOR_TYPE_GRAY) {
bpp = 1;
} else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
bpp = 2;
} else if (color_type == PNG_COLOR_TYPE_RGB || color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
// We use a padding byte even when there is no alpha
bpp = 4;
} else {
printf("Unknown color type %d.\n", color_type);
}
for (j = 0; j < h; j++) {
png_bytep row = rows[j];
for (i = 0; i < w; i++) {
rr = row[0];
gg = row[1];
bb = row[2];
aa = row[3];
row += bpp;
if (i == 0) {
printf("Row %d:", j);
}
switch (bpp) {
case 1:
printf(" (%d)", rr);
break;
case 2:
printf(" (%d %d", rr, gg);
break;
case 3:
printf(" (%d %d %d)", rr, gg, bb);
break;
case 4:
printf(" (%d %d %d %d)", rr, gg, bb, aa);
break;
}
if (i == (w - 1)) {
NOISY(printf("\n"));
}
}
}
}
#define MAX(a,b) ((a)>(b)?(a):(b))
#define ABS(a) ((a)<0?-(a):(a))
static void analyze_image(const char *imageName, image_info &imageInfo, int grayscaleTolerance,
png_colorp rgbPalette, png_bytep alphaPalette,
int *paletteEntries, bool *hasTransparency, int *colorType,
png_bytepp outRows)
{
int w = imageInfo.width;
int h = imageInfo.height;
int i, j, rr, gg, bb, aa, idx;
uint32_t colors[256], col;
int num_colors = 0;
int maxGrayDeviation = 0;
bool isOpaque = true;
bool isPalette = true;
bool isGrayscale = true;
// Scan the entire image and determine if:
// 1. Every pixel has R == G == B (grayscale)
// 2. Every pixel has A == 255 (opaque)
// 3. There are no more than 256 distinct RGBA colors
// NOISY(printf("Initial image data:\n"));
// dump_image(w, h, imageInfo.rows, PNG_COLOR_TYPE_RGB_ALPHA);
for (j = 0; j < h; j++) {
png_bytep row = imageInfo.rows[j];
png_bytep out = outRows[j];
for (i = 0; i < w; i++) {
rr = *row++;
gg = *row++;
bb = *row++;
aa = *row++;
int odev = maxGrayDeviation;
maxGrayDeviation = MAX(ABS(rr - gg), maxGrayDeviation);
maxGrayDeviation = MAX(ABS(gg - bb), maxGrayDeviation);
maxGrayDeviation = MAX(ABS(bb - rr), maxGrayDeviation);
if (maxGrayDeviation > odev) {
NOISY(printf("New max dev. = %d at pixel (%d, %d) = (%d %d %d %d)\n",
maxGrayDeviation, i, j, rr, gg, bb, aa));
}
// Check if image is really grayscale
if (isGrayscale) {
if (rr != gg || rr != bb) {
NOISY(printf("Found a non-gray pixel at %d, %d = (%d %d %d %d)\n",
i, j, rr, gg, bb, aa));
isGrayscale = false;
}
}
// Check if image is really opaque
if (isOpaque) {
if (aa != 0xff) {
NOISY(printf("Found a non-opaque pixel at %d, %d = (%d %d %d %d)\n",
i, j, rr, gg, bb, aa));
isOpaque = false;
}
}
// Check if image is really <= 256 colors
if (isPalette) {
col = (uint32_t) ((rr << 24) | (gg << 16) | (bb << 8) | aa);
bool match = false;
for (idx = 0; idx < num_colors; idx++) {
if (colors[idx] == col) {
match = true;
break;
}
}
// Write the palette index for the pixel to outRows optimistically
// We might overwrite it later if we decide to encode as gray or
// gray + alpha
*out++ = idx;
if (!match) {
if (num_colors == 256) {
NOISY(printf("Found 257th color at %d, %d\n", i, j));
isPalette = false;
} else {
colors[num_colors++] = col;
}
}
}
}
}
*paletteEntries = 0;
*hasTransparency = !isOpaque;
int bpp = isOpaque ? 3 : 4;
int paletteSize = w * h + bpp * num_colors;
NOISY(printf("isGrayscale = %s\n", isGrayscale ? "true" : "false"));
NOISY(printf("isOpaque = %s\n", isOpaque ? "true" : "false"));
NOISY(printf("isPalette = %s\n", isPalette ? "true" : "false"));
NOISY(printf("Size w/ palette = %d, gray+alpha = %d, rgb(a) = %d\n",
paletteSize, 2 * w * h, bpp * w * h));
NOISY(printf("Max gray deviation = %d, tolerance = %d\n", maxGrayDeviation, grayscaleTolerance));
// Choose the best color type for the image.
// 1. Opaque gray - use COLOR_TYPE_GRAY at 1 byte/pixel
// 2. Gray + alpha - use COLOR_TYPE_PALETTE if the number of distinct combinations
// is sufficiently small, otherwise use COLOR_TYPE_GRAY_ALPHA
// 3. RGB(A) - use COLOR_TYPE_PALETTE if the number of distinct colors is sufficiently
// small, otherwise use COLOR_TYPE_RGB{_ALPHA}
if (isGrayscale) {
if (isOpaque) {
*colorType = PNG_COLOR_TYPE_GRAY; // 1 byte/pixel
} else {
// Use a simple heuristic to determine whether using a palette will
// save space versus using gray + alpha for each pixel.
// This doesn't take into account chunk overhead, filtering, LZ
// compression, etc.
if (isPalette && (paletteSize < 2 * w * h)) {
*colorType = PNG_COLOR_TYPE_PALETTE; // 1 byte/pixel + 4 bytes/color
} else {
*colorType = PNG_COLOR_TYPE_GRAY_ALPHA; // 2 bytes per pixel
}
}
} else if (isPalette && (paletteSize < bpp * w * h)) {
*colorType = PNG_COLOR_TYPE_PALETTE;
} else {
if (maxGrayDeviation <= grayscaleTolerance) {
printf("%s: forcing image to gray (max deviation = %d)\n", imageName, maxGrayDeviation);
*colorType = isOpaque ? PNG_COLOR_TYPE_GRAY : PNG_COLOR_TYPE_GRAY_ALPHA;
} else {
*colorType = isOpaque ? PNG_COLOR_TYPE_RGB : PNG_COLOR_TYPE_RGB_ALPHA;
}
}
// Perform postprocessing of the image or palette data based on the final
// color type chosen
if (*colorType == PNG_COLOR_TYPE_PALETTE) {
// Create separate RGB and Alpha palettes and set the number of colors
*paletteEntries = num_colors;
// Create the RGB and alpha palettes
for (int idx = 0; idx < num_colors; idx++) {
col = colors[idx];
rgbPalette[idx].red = (png_byte) ((col >> 24) & 0xff);
rgbPalette[idx].green = (png_byte) ((col >> 16) & 0xff);
rgbPalette[idx].blue = (png_byte) ((col >> 8) & 0xff);
alphaPalette[idx] = (png_byte) (col & 0xff);
}
} else if (*colorType == PNG_COLOR_TYPE_GRAY || *colorType == PNG_COLOR_TYPE_GRAY_ALPHA) {
// If the image is gray or gray + alpha, compact the pixels into outRows
for (j = 0; j < h; j++) {
png_bytep row = imageInfo.rows[j];
png_bytep out = outRows[j];
for (i = 0; i < w; i++) {
rr = *row++;
gg = *row++;
bb = *row++;
aa = *row++;
if (isGrayscale) {
*out++ = rr;
} else {
*out++ = (png_byte) (rr * 0.2126f + gg * 0.7152f + bb * 0.0722f);
}
if (!isOpaque) {
*out++ = aa;
}
}
}
}
}
static void write_png(const char* imageName,
png_structp write_ptr, png_infop write_info,
image_info& imageInfo, int grayscaleTolerance)
{
bool optimize = true;
png_uint_32 width, height;
int color_type;
int bit_depth, interlace_type, compression_type;
int i;
png_unknown_chunk unknowns[3];
unknowns[0].data = NULL;
unknowns[1].data = NULL;
unknowns[2].data = NULL;
png_bytepp outRows = (png_bytepp) malloc((int) imageInfo.height * sizeof(png_bytep));
if (outRows == (png_bytepp) 0) {
printf("Can't allocate output buffer!\n");
exit(1);
}
for (i = 0; i < (int) imageInfo.height; i++) {
outRows[i] = (png_bytep) malloc(2 * (int) imageInfo.width);
if (outRows[i] == (png_bytep) 0) {
printf("Can't allocate output buffer!\n");
exit(1);
}
}
png_set_compression_level(write_ptr, Z_BEST_COMPRESSION);
NOISY(printf("Writing image %s: w = %d, h = %d\n", imageName,
(int) imageInfo.width, (int) imageInfo.height));
png_color rgbPalette[256];
png_byte alphaPalette[256];
bool hasTransparency;
int paletteEntries;
analyze_image(imageName, imageInfo, grayscaleTolerance, rgbPalette, alphaPalette,
&paletteEntries, &hasTransparency, &color_type, outRows);
// If the image is a 9-patch, we need to preserve it as a ARGB file to make
// sure the pixels will not be pre-dithered/clamped until we decide they are
if (imageInfo.is9Patch && (color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_PALETTE)) {
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
}
switch (color_type) {
case PNG_COLOR_TYPE_PALETTE:
NOISY(printf("Image %s has %d colors%s, using PNG_COLOR_TYPE_PALETTE\n",
imageName, paletteEntries,
hasTransparency ? " (with alpha)" : ""));
break;
case PNG_COLOR_TYPE_GRAY:
NOISY(printf("Image %s is opaque gray, using PNG_COLOR_TYPE_GRAY\n", imageName));
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
NOISY(printf("Image %s is gray + alpha, using PNG_COLOR_TYPE_GRAY_ALPHA\n", imageName));
break;
case PNG_COLOR_TYPE_RGB:
NOISY(printf("Image %s is opaque RGB, using PNG_COLOR_TYPE_RGB\n", imageName));
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
NOISY(printf("Image %s is RGB + alpha, using PNG_COLOR_TYPE_RGB_ALPHA\n", imageName));
break;
}
png_set_IHDR(write_ptr, write_info, imageInfo.width, imageInfo.height,
8, color_type, PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
if (color_type == PNG_COLOR_TYPE_PALETTE) {
png_set_PLTE(write_ptr, write_info, rgbPalette, paletteEntries);
if (hasTransparency) {
png_set_tRNS(write_ptr, write_info, alphaPalette, paletteEntries, (png_color_16p) 0);
}
png_set_filter(write_ptr, 0, PNG_NO_FILTERS);
} else {
png_set_filter(write_ptr, 0, PNG_ALL_FILTERS);
}
if (imageInfo.is9Patch) {
int chunk_count = 2 + (imageInfo.haveLayoutBounds ? 1 : 0);
int p_index = imageInfo.haveLayoutBounds ? 2 : 1;
int b_index = 1;
int o_index = 0;
// Chunks ordered thusly because older platforms depend on the base 9 patch data being last
png_byte *chunk_names = imageInfo.haveLayoutBounds
? (png_byte*)"npOl\0npLb\0npTc\0"
: (png_byte*)"npOl\0npTc";
// base 9 patch data
NOISY(printf("Adding 9-patch info...\n"));
strcpy((char*)unknowns[p_index].name, "npTc");
unknowns[p_index].data = (png_byte*)imageInfo.serialize9patch();
unknowns[p_index].size = imageInfo.info9Patch.serializedSize();
// TODO: remove the check below when everything works
checkNinePatchSerialization(&imageInfo.info9Patch, unknowns[p_index].data);
// automatically generated 9 patch outline data
int chunk_size = sizeof(png_uint_32) * 6;
strcpy((char*)unknowns[o_index].name, "npOl");
unknowns[o_index].data = (png_byte*) calloc(chunk_size, 1);
png_byte outputData[chunk_size];
memcpy(&outputData, &imageInfo.outlineInsetsLeft, 4 * sizeof(png_uint_32));
((float*) outputData)[4] = imageInfo.outlineRadius;
((png_uint_32*) outputData)[5] = imageInfo.outlineAlpha;
memcpy(unknowns[o_index].data, &outputData, chunk_size);
unknowns[o_index].size = chunk_size;
// optional optical inset / layout bounds data
if (imageInfo.haveLayoutBounds) {
int chunk_size = sizeof(png_uint_32) * 4;
strcpy((char*)unknowns[b_index].name, "npLb");
unknowns[b_index].data = (png_byte*) calloc(chunk_size, 1);
memcpy(unknowns[b_index].data, &imageInfo.layoutBoundsLeft, chunk_size);
unknowns[b_index].size = chunk_size;
}
for (int i = 0; i < chunk_count; i++) {
unknowns[i].location = PNG_HAVE_PLTE;
}
png_set_keep_unknown_chunks(write_ptr, PNG_HANDLE_CHUNK_ALWAYS,
chunk_names, chunk_count);
png_set_unknown_chunks(write_ptr, write_info, unknowns, chunk_count);
#if PNG_LIBPNG_VER < 10600
/* Deal with unknown chunk location bug in 1.5.x and earlier */
png_set_unknown_chunk_location(write_ptr, write_info, 0, PNG_HAVE_PLTE);
if (imageInfo.haveLayoutBounds) {
png_set_unknown_chunk_location(write_ptr, write_info, 1, PNG_HAVE_PLTE);
}
#endif
}
png_write_info(write_ptr, write_info);
png_bytepp rows;
if (color_type == PNG_COLOR_TYPE_RGB || color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
if (color_type == PNG_COLOR_TYPE_RGB) {
png_set_filler(write_ptr, 0, PNG_FILLER_AFTER);
}
rows = imageInfo.rows;
} else {
rows = outRows;
}
png_write_image(write_ptr, rows);
// NOISY(printf("Final image data:\n"));
// dump_image(imageInfo.width, imageInfo.height, rows, color_type);
png_write_end(write_ptr, write_info);
for (i = 0; i < (int) imageInfo.height; i++) {
free(outRows[i]);
}
free(outRows);
free(unknowns[0].data);
free(unknowns[1].data);
free(unknowns[2].data);
png_get_IHDR(write_ptr, write_info, &width, &height,
&bit_depth, &color_type, &interlace_type,
&compression_type, NULL);
NOISY(printf("Image written: w=%d, h=%d, d=%d, colors=%d, inter=%d, comp=%d\n",
(int)width, (int)height, bit_depth, color_type, interlace_type,
compression_type));
}
status_t preProcessImage(const Bundle* bundle, const sp<AaptAssets>& assets,
const sp<AaptFile>& file, String8* outNewLeafName)
{
String8 ext(file->getPath().getPathExtension());
// We currently only process PNG images.
if (strcmp(ext.string(), ".png") != 0) {
return NO_ERROR;
}
// Example of renaming a file:
//*outNewLeafName = file->getPath().getBasePath().getFileName();
//outNewLeafName->append(".nupng");
String8 printableName(file->getPrintableSource());
if (bundle->getVerbose()) {
printf("Processing image: %s\n", printableName.string());
}
png_structp read_ptr = NULL;
png_infop read_info = NULL;
FILE* fp;
image_info imageInfo;
png_structp write_ptr = NULL;
png_infop write_info = NULL;
status_t error = UNKNOWN_ERROR;
const size_t nameLen = file->getPath().length();
fp = fopen(file->getSourceFile().string(), "rb");
if (fp == NULL) {
fprintf(stderr, "%s: ERROR: Unable to open PNG file\n", printableName.string());
goto bail;
}
read_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, (png_error_ptr)NULL,
(png_error_ptr)NULL);
if (!read_ptr) {
goto bail;
}
read_info = png_create_info_struct(read_ptr);
if (!read_info) {
goto bail;
}
if (setjmp(png_jmpbuf(read_ptr))) {
goto bail;
}
png_init_io(read_ptr, fp);
read_png(printableName.string(), read_ptr, read_info, &imageInfo);
if (nameLen > 6) {
const char* name = file->getPath().string();
if (name[nameLen-5] == '9' && name[nameLen-6] == '.') {
if (do_9patch(printableName.string(), &imageInfo) != NO_ERROR) {
goto bail;
}
}
}
write_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, 0, (png_error_ptr)NULL,
(png_error_ptr)NULL);
if (!write_ptr)
{
goto bail;
}
write_info = png_create_info_struct(write_ptr);
if (!write_info)
{
goto bail;
}
png_set_write_fn(write_ptr, (void*)file.get(),
png_write_aapt_file, png_flush_aapt_file);
if (setjmp(png_jmpbuf(write_ptr)))
{
goto bail;
}
write_png(printableName.string(), write_ptr, write_info, imageInfo,
bundle->getGrayscaleTolerance());
error = NO_ERROR;
if (bundle->getVerbose()) {
fseek(fp, 0, SEEK_END);
size_t oldSize = (size_t)ftell(fp);
size_t newSize = file->getSize();
float factor = ((float)newSize)/oldSize;
int percent = (int)(factor*100);
printf(" (processed image %s: %d%% size of source)\n", printableName.string(), percent);
}
bail:
if (read_ptr) {
png_destroy_read_struct(&read_ptr, &read_info, (png_infopp)NULL);
}
if (fp) {
fclose(fp);
}
if (write_ptr) {
png_destroy_write_struct(&write_ptr, &write_info);
}
if (error != NO_ERROR) {
fprintf(stderr, "ERROR: Failure processing PNG image %s\n",
file->getPrintableSource().string());
}
return error;
}
status_t preProcessImageToCache(const Bundle* bundle, const String8& source, const String8& dest)
{
png_structp read_ptr = NULL;
png_infop read_info = NULL;
FILE* fp;
image_info imageInfo;
png_structp write_ptr = NULL;
png_infop write_info = NULL;
status_t error = UNKNOWN_ERROR;
if (bundle->getVerbose()) {
printf("Processing image to cache: %s => %s\n", source.string(), dest.string());
}
// Get a file handler to read from
fp = fopen(source.string(),"rb");
if (fp == NULL) {
fprintf(stderr, "%s ERROR: Unable to open PNG file\n", source.string());
return error;
}
// Call libpng to get a struct to read image data into
read_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!read_ptr) {
fclose(fp);
png_destroy_read_struct(&read_ptr, &read_info,NULL);
return error;
}
// Call libpng to get a struct to read image info into
read_info = png_create_info_struct(read_ptr);
if (!read_info) {
fclose(fp);
png_destroy_read_struct(&read_ptr, &read_info,NULL);
return error;
}
// Set a jump point for libpng to long jump back to on error
if (setjmp(png_jmpbuf(read_ptr))) {
fclose(fp);
png_destroy_read_struct(&read_ptr, &read_info,NULL);
return error;
}
// Set up libpng to read from our file.
png_init_io(read_ptr,fp);
// Actually read data from the file
read_png(source.string(), read_ptr, read_info, &imageInfo);
// We're done reading so we can clean up
// Find old file size before releasing handle
fseek(fp, 0, SEEK_END);
size_t oldSize = (size_t)ftell(fp);
fclose(fp);
png_destroy_read_struct(&read_ptr, &read_info,NULL);
// Check to see if we're dealing with a 9-patch
// If we are, process appropriately
if (source.getBasePath().getPathExtension() == ".9") {
if (do_9patch(source.string(), &imageInfo) != NO_ERROR) {
return error;
}
}
// Call libpng to create a structure to hold the processed image data
// that can be written to disk
write_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!write_ptr) {
png_destroy_write_struct(&write_ptr, &write_info);
return error;
}
// Call libpng to create a structure to hold processed image info that can
// be written to disk
write_info = png_create_info_struct(write_ptr);
if (!write_info) {
png_destroy_write_struct(&write_ptr, &write_info);
return error;
}
// Open up our destination file for writing
fp = fopen(dest.string(), "wb");
if (!fp) {
fprintf(stderr, "%s ERROR: Unable to open PNG file\n", dest.string());
png_destroy_write_struct(&write_ptr, &write_info);
return error;
}
// Set up libpng to write to our file
png_init_io(write_ptr, fp);
// Set up a jump for libpng to long jump back on on errors
if (setjmp(png_jmpbuf(write_ptr))) {
fclose(fp);
png_destroy_write_struct(&write_ptr, &write_info);
return error;
}
// Actually write out to the new png
write_png(dest.string(), write_ptr, write_info, imageInfo,
bundle->getGrayscaleTolerance());
if (bundle->getVerbose()) {
// Find the size of our new file
FILE* reader = fopen(dest.string(), "rb");
fseek(reader, 0, SEEK_END);
size_t newSize = (size_t)ftell(reader);
fclose(reader);
float factor = ((float)newSize)/oldSize;
int percent = (int)(factor*100);
printf(" (processed image to cache entry %s: %d%% size of source)\n",
dest.string(), percent);
}
//Clean up
fclose(fp);
png_destroy_write_struct(&write_ptr, &write_info);
return NO_ERROR;
}
status_t postProcessImage(const Bundle* bundle, const sp<AaptAssets>& assets,
ResourceTable* table, const sp<AaptFile>& file)
{
String8 ext(file->getPath().getPathExtension());
// At this point, now that we have all the resource data, all we need to
// do is compile XML files.
if (strcmp(ext.string(), ".xml") == 0) {
String16 resourceName(parseResourceName(file->getPath().getPathLeaf()));
return compileXmlFile(bundle, assets, resourceName, file, table);
}
return NO_ERROR;
}
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