SourceBuffer::SourceBuffer(MediaSource* aMediaSource, const nsACString& aType)
: DOMEventTargetHelper(aMediaSource->GetParentObject())
, mMediaSource(aMediaSource)
, mType(aType)
, mAppendWindowStart(0)
, mAppendWindowEnd(PositiveInfinity<double>())
, mTimestampOffset(0)
, mAppendMode(SourceBufferAppendMode::Segments)
, mUpdating(false)
, mDecoderInitialized(false)
{
MOZ_ASSERT(aMediaSource);
mParser = ContainerParser::CreateForMIMEType(aType);
MSE_DEBUG("%p SourceBuffer: Creating initial decoder.", this);
InitNewDecoder();
}
void
SourceBuffer::AppendData(const uint8_t* aData, uint32_t aLength, ErrorResult& aRv)
{
MSE_DEBUG("SourceBuffer(%p)::AppendData(aLength=%u)", this, aLength);
if (!IsAttached() || mUpdating) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return;
}
if (mMediaSource->ReadyState() == MediaSourceReadyState::Ended) {
mMediaSource->SetReadyState(MediaSourceReadyState::Open);
}
// TODO: Run coded frame eviction algorithm.
// TODO: Test buffer full flag.
StartUpdating();
// TODO: Run buffer append algorithm asynchronously (would call StopUpdating()).
if (mParser->IsInitSegmentPresent(aData, aLength)) {
MSE_DEBUG("SourceBuffer(%p)::AppendData: New initialization segment.", this);
if (mDecoderInitialized) {
// Existing decoder has been used, time for a new one.
DiscardDecoder();
}
// If we've got a decoder here, it's not initialized, so we can use it
// rather than creating a new one.
if (!mDecoder && !InitNewDecoder()) {
aRv.Throw(NS_ERROR_FAILURE); // XXX: Review error handling.
return;
}
MSE_DEBUG("SourceBuffer(%p)::AppendData: Decoder marked as initialized.", this);
mDecoderInitialized = true;
} else if (!mDecoderInitialized) {
MSE_DEBUG("SourceBuffer(%p)::AppendData: Non-init segment appended during initialization.");
Optional<MediaSourceEndOfStreamError> decodeError(MediaSourceEndOfStreamError::Decode);
ErrorResult dummy;
mMediaSource->EndOfStream(decodeError, dummy);
aRv.Throw(NS_ERROR_FAILURE);
return;
}
// XXX: For future reference: NDA call must run on the main thread.
mDecoder->NotifyDataArrived(reinterpret_cast<const char*>(aData),
aLength,
mDecoder->GetResource()->GetLength());
mDecoder->GetResource()->AppendData(aData, aLength);
// Eviction uses a byte threshold. If the buffer is greater than the
// number of bytes then data is evicted. The time range for this
// eviction is reported back to the media source. It will then
// evict data before that range across all SourceBuffers it knows
// about.
// TODO: Make the eviction threshold smaller for audio-only streams.
// TODO: Drive evictions off memory pressure notifications.
const uint32_t evict_threshold = 75 * (1 << 20);
bool evicted = mDecoder->GetResource()->EvictData(evict_threshold);
if (evicted) {
MSE_DEBUG("SourceBuffer(%p)::AppendBuffer Evict; current buffered start=%f",
this, GetBufferedStart());
// We notify that we've evicted from the time range 0 through to
// the current start point.
mMediaSource->NotifyEvicted(0.0, GetBufferedStart());
}
StopUpdating();
// Schedule the state machine thread to ensure playback starts
// if required when data is appended.
mMediaSource->GetDecoder()->ScheduleStateMachineThread();
mMediaSource->NotifyGotData();
}