virtual void ProcessBlock(AudioNodeStream* aStream,
const AudioChunk& aInput,
AudioChunk* aOutput,
bool* aFinished)
{
if (!mBuffer || !mBufferEnd) {
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
uint32_t channels = mBuffer->GetChannels();
if (!channels) {
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
// WebKit treats the playbackRate as a k-rate parameter in their code,
// despite the spec saying that it should be an a-rate parameter. We treat
// it as k-rate. Spec bug: https://www.w3.org/Bugs/Public/show_bug.cgi?id=21592
UpdateSampleRateIfNeeded(channels);
uint32_t written = 0;
TrackTicks streamPosition = aStream->GetCurrentPosition();
while (written < WEBAUDIO_BLOCK_SIZE) {
if (mStop != TRACK_TICKS_MAX &&
streamPosition >= mStop) {
FillWithZeroes(aOutput, channels, &written, &streamPosition, TRACK_TICKS_MAX);
continue;
}
if (streamPosition < mBeginProcessing) {
FillWithZeroes(aOutput, channels, &written, &streamPosition,
mBeginProcessing);
continue;
}
if (mLoop) {
// mLoopEnd can become less than mBufferPosition when a LOOPEND engine
// parameter is received after "loopend" is changed on the node or a
// new buffer with lower samplerate is set.
if (mBufferPosition >= mLoopEnd) {
mBufferPosition = mLoopStart;
}
CopyFromBuffer(aStream, aOutput, channels, &written, &streamPosition, mLoopEnd);
} else {
if (mBufferPosition < mBufferEnd || mRemainingResamplerTail) {
CopyFromBuffer(aStream, aOutput, channels, &written, &streamPosition, mBufferEnd);
} else {
FillWithZeroes(aOutput, channels, &written, &streamPosition, TRACK_TICKS_MAX);
}
}
}
// We've finished if we've gone past mStop, or if we're past mDuration when
// looping is disabled.
if (streamPosition >= mStop ||
(!mLoop && mBufferPosition >= mBufferEnd && !mRemainingResamplerTail)) {
*aFinished = true;
}
}
virtual void ProduceAudioBlock(AudioNodeStream* aStream,
const AudioChunk& aInput,
AudioChunk* aOutput,
bool* aFinished)
{
if (!mBuffer || !mDuration) {
return;
}
uint32_t channels = mBuffer->GetChannels();
if (!channels) {
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
// WebKit treats the playbackRate as a k-rate parameter in their code,
// despite the spec saying that it should be an a-rate parameter. We treat
// it as k-rate. Spec bug: https://www.w3.org/Bugs/Public/show_bug.cgi?id=21592
UpdateSampleRateIfNeeded(aStream, channels);
uint32_t written = 0;
TrackTicks currentPosition = GetPosition(aStream);
while (written < WEBAUDIO_BLOCK_SIZE) {
if (mStop != TRACK_TICKS_MAX &&
currentPosition >= mStop) {
FillWithZeroes(aOutput, channels, &written, ¤tPosition, TRACK_TICKS_MAX);
continue;
}
if (currentPosition < mStart) {
FillWithZeroes(aOutput, channels, &written, ¤tPosition, mStart);
continue;
}
TrackTicks t = currentPosition - mStart;
if (mLoop) {
if (mOffset + t < mLoopEnd) {
CopyFromBuffer(aStream, aOutput, channels, &written, ¤tPosition, mOffset + t, mLoopEnd);
} else {
uint32_t offsetInLoop = (mOffset + t - mLoopEnd) % (mLoopEnd - mLoopStart);
CopyFromBuffer(aStream, aOutput, channels, &written, ¤tPosition, mLoopStart + offsetInLoop, mLoopEnd);
}
} else {
if (mOffset + t < mDuration) {
CopyFromBuffer(aStream, aOutput, channels, &written, ¤tPosition, mOffset + t, mDuration);
} else {
FillWithZeroes(aOutput, channels, &written, ¤tPosition, TRACK_TICKS_MAX);
}
}
}
// We've finished if we've gone past mStop, or if we're past mDuration when
// looping is disabled.
if (currentPosition >= mStop ||
(!mLoop && currentPosition - mStart + mOffset > mDuration)) {
*aFinished = true;
}
}
void ProcessBlock(AudioNodeStream* aStream,
GraphTime aFrom,
const AudioBlock& aInput,
AudioBlock* aOutput,
bool* aFinished) override
{
if (mBufferSampleRate == 0) {
// start() has not yet been called or no buffer has yet been set
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
StreamTime streamPosition = mDestination->GraphTimeToStreamTime(aFrom);
uint32_t channels = mBuffer.ChannelCount();
UpdateSampleRateIfNeeded(channels, streamPosition);
uint32_t written = 0;
while (written < WEBAUDIO_BLOCK_SIZE) {
if (mStop != STREAM_TIME_MAX &&
streamPosition >= mStop) {
FillWithZeroes(aOutput, channels, &written, &streamPosition, STREAM_TIME_MAX);
continue;
}
if (streamPosition < mBeginProcessing) {
FillWithZeroes(aOutput, channels, &written, &streamPosition,
mBeginProcessing);
continue;
}
if (mLoop) {
// mLoopEnd can become less than mBufferPosition when a LOOPEND engine
// parameter is received after "loopend" is changed on the node or a
// new buffer with lower samplerate is set.
if (mBufferPosition >= mLoopEnd) {
mBufferPosition = mLoopStart;
}
CopyFromBuffer(aOutput, channels, &written, &streamPosition, mLoopEnd);
} else {
if (mBufferPosition < mBufferEnd || mRemainingResamplerTail) {
CopyFromBuffer(aOutput, channels, &written, &streamPosition, mBufferEnd);
} else {
FillWithZeroes(aOutput, channels, &written, &streamPosition, STREAM_TIME_MAX);
}
}
}
// We've finished if we've gone past mStop, or if we're past mDuration when
// looping is disabled.
if (streamPosition >= mStop ||
(!mLoop && mBufferPosition >= mBufferEnd && !mRemainingResamplerTail)) {
*aFinished = true;
}
}