/**
* Converts the data in aSegment to a single chunk aBlock. aSegment must have
* duration WEBAUDIO_BLOCK_SIZE. aFallbackChannelCount is a superset of the
* channels in every chunk of aSegment. aBlock must be float format or null.
*/
static void ConvertSegmentToAudioBlock(AudioSegment* aSegment,
AudioChunk* aBlock,
int32_t aFallbackChannelCount)
{
NS_ASSERTION(aSegment->GetDuration() == WEBAUDIO_BLOCK_SIZE, "Bad segment duration");
{
AudioSegment::ChunkIterator ci(*aSegment);
NS_ASSERTION(!ci.IsEnded(), "Should be at least one chunk!");
if (ci->GetDuration() == WEBAUDIO_BLOCK_SIZE &&
(ci->IsNull() || ci->mBufferFormat == AUDIO_FORMAT_FLOAT32)) {
// Return this chunk directly to avoid copying data.
*aBlock = *ci;
return;
}
}
AllocateAudioBlock(aFallbackChannelCount, aBlock);
uint32_t duration = 0;
for (AudioSegment::ChunkIterator ci(*aSegment); !ci.IsEnded(); ci.Next()) {
CopyChunkToBlock(*ci, aBlock, duration);
duration += ci->GetDuration();
}
}
/**
* Converts the data in aSegment to a single chunk aChunk. Every chunk in
* aSegment must have the same number of channels (or be null). aSegment must have
* duration WEBAUDIO_BLOCK_SIZE. Every chunk in aSegment must be in float format.
*/
static void
ConvertSegmentToAudioBlock(AudioSegment* aSegment, AudioChunk* aBlock)
{
NS_ASSERTION(aSegment->GetDuration() == WEBAUDIO_BLOCK_SIZE, "Bad segment duration");
{
AudioSegment::ChunkIterator ci(*aSegment);
NS_ASSERTION(!ci.IsEnded(), "Segment must have at least one chunk");
AudioChunk& firstChunk = *ci;
ci.Next();
if (ci.IsEnded()) {
*aBlock = firstChunk;
return;
}
while (ci->IsNull() && !ci.IsEnded()) {
ci.Next();
}
if (ci.IsEnded()) {
// All null.
aBlock->SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
AllocateAudioBlock(ci->mChannelData.Length(), aBlock);
}
AudioSegment::ChunkIterator ci(*aSegment);
uint32_t duration = 0;
while (!ci.IsEnded()) {
CopyChunkToBlock(*ci, aBlock, duration);
duration += ci->GetDuration();
ci.Next();
}
}
