18db49a462
Fix indentation to be multiple of 4. Make it easier to search: sp< not sp < to "switch (...)" instead of "switch(...)" (also "if" and "while") Remove redundant blank line at start or EOF. Remove whitespace at end of line. Remove extra blank lines where they don't add value. Use git diff -b or -w to verify. Change-Id: I966b7ba852faa5474be6907fb212f5e267c2874e
69 lines
2.4 KiB
C++
69 lines
2.4 KiB
C++
/*
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* Copyright (C) 2007 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef ANDROID_AUDIO_RESAMPLER_CUBIC_H
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#define ANDROID_AUDIO_RESAMPLER_CUBIC_H
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#include <stdint.h>
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#include <sys/types.h>
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#include <cutils/log.h>
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#include "AudioResampler.h"
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namespace android {
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// ----------------------------------------------------------------------------
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class AudioResamplerCubic : public AudioResampler {
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public:
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AudioResamplerCubic(int bitDepth, int inChannelCount, int32_t sampleRate) :
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AudioResampler(bitDepth, inChannelCount, sampleRate) {
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}
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virtual void resample(int32_t* out, size_t outFrameCount,
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AudioBufferProvider* provider);
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private:
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// number of bits used in interpolation multiply - 14 bits avoids overflow
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static const int kNumInterpBits = 14;
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// bits to shift the phase fraction down to avoid overflow
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static const int kPreInterpShift = kNumPhaseBits - kNumInterpBits;
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typedef struct {
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int32_t a, b, c, y0, y1, y2, y3;
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} state;
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void init();
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void resampleMono16(int32_t* out, size_t outFrameCount,
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AudioBufferProvider* provider);
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void resampleStereo16(int32_t* out, size_t outFrameCount,
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AudioBufferProvider* provider);
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static inline int32_t interp(state* p, int32_t x) {
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return (((((p->a * x >> 14) + p->b) * x >> 14) + p->c) * x >> 14) + p->y1;
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}
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static inline void advance(state* p, int16_t in) {
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p->y0 = p->y1;
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p->y1 = p->y2;
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p->y2 = p->y3;
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p->y3 = in;
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p->a = (3 * (p->y1 - p->y2) - p->y0 + p->y3) >> 1;
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p->b = (p->y2 << 1) + p->y0 - (((5 * p->y1 + p->y3)) >> 1);
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p->c = (p->y2 - p->y0) >> 1;
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}
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state left, right;
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};
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// ----------------------------------------------------------------------------
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}; // namespace android
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#endif /*ANDROID_AUDIO_RESAMPLER_CUBIC_H*/
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