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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
#include "DynamicResampler.h"
namespace mozilla {
DynamicResampler::DynamicResampler(uint32_t aInRate, uint32_t aOutRate,
uint32_t aInputPreBufferFrameCount)
: mOutRate(aOutRate),
mInputPreBufferFrameCount(aInputPreBufferFrameCount),
mInRate(aInRate) {
MOZ_ASSERT(aInRate);
MOZ_ASSERT(aOutRate);
UpdateResampler(mInRate, STEREO);
mInputStreamFile.Open("DynamicResamplerInFirstChannel", 1, mInRate);
mOutputStreamFile.Open("DynamicResamplerOutFirstChannel", 1, mOutRate);
}
DynamicResampler::~DynamicResampler() {
if (mResampler) {
speex_resampler_destroy(mResampler);
}
}
void DynamicResampler::SetSampleFormat(AudioSampleFormat aFormat) {
MOZ_ASSERT(mSampleFormat == AUDIO_FORMAT_SILENCE);
MOZ_ASSERT(aFormat == AUDIO_FORMAT_S16 || aFormat == AUDIO_FORMAT_FLOAT32);
mSampleFormat = aFormat;
for (AudioRingBuffer& b : mInternalInBuffer) {
b.SetSampleFormat(mSampleFormat);
}
// Pre-allocate something big.
// EnsureInputBufferDuration() adds 50ms for jitter to this first allocation
// so the 50ms argument means at least 100ms.
EnsureInputBufferSizeInFrames(mInRate / 20);
}
void DynamicResampler::EnsurePreBuffer(media::TimeUnit aDuration) {
if (mIsPreBufferSet) {
return;
}
uint32_t buffered = mInternalInBuffer[0].AvailableRead();
if (buffered == 0) {
// Wait for the first input segment before deciding how much to pre-buffer.
// If it is large it indicates high-latency, and the buffer would have to
// handle that. This also means that the pre-buffer is not set up just
// before a large input segment would extend the buffering beyond the
// desired level.
return;
}
mIsPreBufferSet = true;
uint32_t needed =
aDuration.ToTicksAtRate(mInRate) + mInputPreBufferFrameCount;
EnsureInputBufferSizeInFrames(needed);
if (needed > buffered) {
for (auto& b : mInternalInBuffer) {
b.PrependSilence(needed - buffered);
}
} else if (needed < buffered) {
for (auto& b : mInternalInBuffer) {
b.Discard(buffered - needed);
}
}
}
void DynamicResampler::SetInputPreBufferFrameCount(
uint32_t aInputPreBufferFrameCount) {
mInputPreBufferFrameCount = aInputPreBufferFrameCount;
}
bool DynamicResampler::Resample(float* aOutBuffer, uint32_t aOutFrames,
uint32_t aChannelIndex) {
MOZ_ASSERT(mSampleFormat == AUDIO_FORMAT_FLOAT32);
return ResampleInternal(aOutBuffer, aOutFrames, aChannelIndex);
}
bool DynamicResampler::Resample(int16_t* aOutBuffer, uint32_t aOutFrames,
uint32_t aChannelIndex) {
MOZ_ASSERT(mSampleFormat == AUDIO_FORMAT_S16);
return ResampleInternal(aOutBuffer, aOutFrames, aChannelIndex);
}
void DynamicResampler::ResampleInternal(const float* aInBuffer,
uint32_t* aInFrames, float* aOutBuffer,
uint32_t* aOutFrames,
uint32_t aChannelIndex) {
MOZ_ASSERT(mResampler);
MOZ_ASSERT(mChannels);
MOZ_ASSERT(mInRate);
MOZ_ASSERT(mOutRate);
MOZ_ASSERT(aInFrames);
MOZ_ASSERT(*aInFrames > 0);
MOZ_ASSERT(aOutBuffer);
MOZ_ASSERT(aOutFrames);
MOZ_ASSERT(*aOutFrames > 0);
MOZ_ASSERT(aChannelIndex <= mChannels);
#ifdef DEBUG
int rv =
#endif
speex_resampler_process_float(mResampler, aChannelIndex, aInBuffer,
aInFrames, aOutBuffer, aOutFrames);
MOZ_ASSERT(rv == RESAMPLER_ERR_SUCCESS);
if (aChannelIndex == 0 && !mIsWarmingUp) {
mInputStreamFile.Write(aInBuffer, *aInFrames);
mOutputStreamFile.Write(aOutBuffer, *aOutFrames);
}
}
void DynamicResampler::ResampleInternal(const int16_t* aInBuffer,
uint32_t* aInFrames,
int16_t* aOutBuffer,
uint32_t* aOutFrames,
uint32_t aChannelIndex) {
MOZ_ASSERT(mResampler);
MOZ_ASSERT(mChannels);
MOZ_ASSERT(mInRate);
MOZ_ASSERT(mOutRate);
MOZ_ASSERT(aInFrames);
MOZ_ASSERT(*aInFrames > 0);
MOZ_ASSERT(aOutBuffer);
MOZ_ASSERT(aOutFrames);
MOZ_ASSERT(*aOutFrames > 0);
MOZ_ASSERT(aChannelIndex <= mChannels);
#ifdef DEBUG
int rv =
#endif
speex_resampler_process_int(mResampler, aChannelIndex, aInBuffer,
aInFrames, aOutBuffer, aOutFrames);
MOZ_ASSERT(rv == RESAMPLER_ERR_SUCCESS);
if (aChannelIndex == 0 && !mIsWarmingUp) {
mInputStreamFile.Write(aInBuffer, *aInFrames);
mOutputStreamFile.Write(aOutBuffer, *aOutFrames);
}
}
void DynamicResampler::UpdateResampler(uint32_t aInRate, uint32_t aChannels) {
MOZ_ASSERT(aInRate);
MOZ_ASSERT(aChannels);
if (mChannels != aChannels) {
uint32_t bufferSizeInFrames = InFramesBufferSize();
if (mResampler) {
speex_resampler_destroy(mResampler);
}
mResampler = speex_resampler_init(aChannels, aInRate, mOutRate,
SPEEX_RESAMPLER_QUALITY_MIN, nullptr);
MOZ_ASSERT(mResampler);
mChannels = aChannels;
mInRate = aInRate;
mResamplerIsBypassed &= aInRate == mOutRate;
// Between mono and stereo changes, keep always allocated 2 channels to
// avoid reallocations in the most common case.
if ((mChannels == STEREO || mChannels == 1) &&
mInternalInBuffer.Length() == STEREO) {
// Don't worry if format is not set it will write silence then.
if ((mSampleFormat == AUDIO_FORMAT_S16 ||
mSampleFormat == AUDIO_FORMAT_FLOAT32) &&
mChannels == STEREO) {
// The mono channel is always up to date. When we are going from mono
// to stereo upmix the mono to stereo channel
uint32_t bufferedDuration = mInternalInBuffer[0].AvailableRead();
mInternalInBuffer[1].Clear();
if (bufferedDuration) {
mInternalInBuffer[1].Write(mInternalInBuffer[0], bufferedDuration);
}
}
// Maintain stereo size
mInputTail.SetLength(STEREO);
WarmUpResampler(false);
return;
}
// upmix or downmix, for now just clear but it has to be updated
// because allocates and this is executed in audio thread.
mInternalInBuffer.Clear();
for (uint32_t i = 0; i < mChannels; ++i) {
AudioRingBuffer* b = mInternalInBuffer.AppendElement(0);
if (mSampleFormat != AUDIO_FORMAT_SILENCE) {
// In ctor this update is not needed
b->SetSampleFormat(mSampleFormat);
}
}
EnsureInputBufferSizeInFrames(bufferSizeInFrames);
mInputTail.SetLength(mChannels);
return;
}
if (mInRate != aInRate) {
// If the rates was the same the resampler was not being used so warm up.
if (mResamplerIsBypassed) {
mResamplerIsBypassed = false;
WarmUpResampler(true);
}
#ifdef DEBUG
int rv =
#endif
speex_resampler_set_rate(mResampler, aInRate, mOutRate);
MOZ_ASSERT(rv == RESAMPLER_ERR_SUCCESS);
mInRate = aInRate;
}
}
void DynamicResampler::WarmUpResampler(bool aSkipLatency) {
MOZ_ASSERT(mInputTail.Length());
mIsWarmingUp = true;
for (uint32_t i = 0; i < mChannels; ++i) {
if (!mInputTail[i].Length()) {
continue;
}
uint32_t inFrames = mInputTail[i].Length();
uint32_t outFrames = 5 * TailBuffer::MAXSIZE; // something big
if (mSampleFormat == AUDIO_FORMAT_S16) {
short outBuffer[5 * TailBuffer::MAXSIZE] = {};
ResampleInternal(mInputTail[i].Buffer<short>(), &inFrames, outBuffer,
&outFrames, i);
MOZ_ASSERT(inFrames == (uint32_t)mInputTail[i].Length());
} else {
float outBuffer[100] = {};
ResampleInternal(mInputTail[i].Buffer<float>(), &inFrames, outBuffer,
&outFrames, i);
MOZ_ASSERT(inFrames == (uint32_t)mInputTail[i].Length());
}
}
if (aSkipLatency) {
// Don't generate output frames corresponding to times before the next
// input sample.
speex_resampler_skip_zeros(mResampler);
}
mIsWarmingUp = false;
}
void DynamicResampler::AppendInput(Span<const float* const> aInBuffer,
uint32_t aInFrames) {
MOZ_ASSERT(mSampleFormat == AUDIO_FORMAT_FLOAT32);
AppendInputInternal(aInBuffer, aInFrames);
}
void DynamicResampler::AppendInput(Span<const int16_t* const> aInBuffer,
uint32_t aInFrames) {
MOZ_ASSERT(mSampleFormat == AUDIO_FORMAT_S16);
AppendInputInternal(aInBuffer, aInFrames);
}
void DynamicResampler::AppendInputSilence(const uint32_t aInFrames) {
MOZ_ASSERT(aInFrames);
MOZ_ASSERT(mChannels);
MOZ_ASSERT(mInternalInBuffer.Length() >= (uint32_t)mChannels);
for (uint32_t i = 0; i < mChannels; ++i) {
mInternalInBuffer[i].WriteSilence(aInFrames);
}
}
uint32_t DynamicResampler::InFramesBufferSize() const {
if (mSampleFormat == AUDIO_FORMAT_SILENCE) {
return 0;
}
// Buffers may have different capacities if a memory allocation has failed.
MOZ_ASSERT(!mInternalInBuffer.IsEmpty());
uint32_t min = std::numeric_limits<uint32_t>::max();
for (const auto& b : mInternalInBuffer) {
min = std::min(min, b.Capacity());
}
return min;
}
uint32_t DynamicResampler::InFramesBuffered(uint32_t aChannelIndex) const {
MOZ_ASSERT(mChannels);
MOZ_ASSERT(aChannelIndex <= mChannels);
MOZ_ASSERT(aChannelIndex <= mInternalInBuffer.Length());
if (!mIsPreBufferSet) {
return mInputPreBufferFrameCount;
}
return mInternalInBuffer[aChannelIndex].AvailableRead();
}
} // namespace mozilla