C++ MediaStream::GraphTimeToStreamTime方法代码示例

  void TrackUnionStream::CopyTrackData(StreamBuffer::Track* aInputTrack,
                     uint32_t aMapIndex, GraphTime aFrom, GraphTime aTo,
                     bool* aOutputTrackFinished)
  {
    TrackMapEntry* map = &mTrackMap[aMapIndex];
    StreamBuffer::Track* outputTrack = mBuffer.FindTrack(map->mOutputTrackID);
    MOZ_ASSERT(outputTrack && !outputTrack->IsEnded(), "Can't copy to ended track");

    MediaSegment* segment = map->mSegment;
    MediaStream* source = map->mInputPort->GetSource();

    GraphTime next;
    *aOutputTrackFinished = false;
    for (GraphTime t = aFrom; t < aTo; t = next) {
      MediaInputPort::InputInterval interval = map->mInputPort->GetNextInputInterval(t);
      interval.mEnd = std::min(interval.mEnd, aTo);
      StreamTime inputEnd = source->GraphTimeToStreamTime(interval.mEnd);
      StreamTime inputTrackEndPoint = STREAM_TIME_MAX;

      if (aInputTrack->IsEnded() &&
          aInputTrack->GetEnd() <= inputEnd) {
        inputTrackEndPoint = aInputTrack->GetEnd();
        *aOutputTrackFinished = true;
      }

      if (interval.mStart >= interval.mEnd) {
        break;
      }
      StreamTime ticks = interval.mEnd - interval.mStart;
      next = interval.mEnd;

      StreamTime outputStart = outputTrack->GetEnd();

      if (interval.mInputIsBlocked) {
        // Maybe the input track ended?
        segment->AppendNullData(ticks);
        STREAM_LOG(PR_LOG_DEBUG+1, ("TrackUnionStream %p appending %lld ticks of null data to track %d",
                   this, (long long)ticks, outputTrack->GetID()));
      } else if (InMutedCycle()) {
        segment->AppendNullData(ticks);
      } else {
        MOZ_ASSERT(outputTrack->GetEnd() == GraphTimeToStreamTime(interval.mStart),
                   "Samples missing");
        StreamTime inputStart = source->GraphTimeToStreamTime(interval.mStart);
        segment->AppendSlice(*aInputTrack->GetSegment(),
                             std::min(inputTrackEndPoint, inputStart),
                             std::min(inputTrackEndPoint, inputEnd));
      }
      ApplyTrackDisabling(outputTrack->GetID(), segment);
      for (uint32_t j = 0; j < mListeners.Length(); ++j) {
        MediaStreamListener* l = mListeners[j];
        l->NotifyQueuedTrackChanges(Graph(), outputTrack->GetID(),
                                    outputStart, 0, *segment);
      }
      outputTrack->GetSegment()->AppendFrom(segment);
    }
  }

void
AudioNodeExternalInputStream::ProcessInput(GraphTime aFrom, GraphTime aTo,
                                           uint32_t aFlags)
{
  // According to spec, number of outputs is always 1.
  MOZ_ASSERT(mLastChunks.Length() == 1);

  // GC stuff can result in our input stream being destroyed before this stream.
  // Handle that.
  if (!IsEnabled() || mInputs.IsEmpty() || mPassThrough) {
    mLastChunks[0].SetNull(WEBAUDIO_BLOCK_SIZE);
    AdvanceOutputSegment();
    return;
  }

  MOZ_ASSERT(mInputs.Length() == 1);

  MediaStream* source = mInputs[0]->GetSource();
  nsAutoTArray<AudioSegment,1> audioSegments;
  uint32_t inputChannels = 0;
  for (StreamBuffer::TrackIter tracks(source->mBuffer, MediaSegment::AUDIO);
       !tracks.IsEnded(); tracks.Next()) {
    const StreamBuffer::Track& inputTrack = *tracks;
    const AudioSegment& inputSegment =
        *static_cast<AudioSegment*>(inputTrack.GetSegment());
    if (inputSegment.IsNull()) {
      continue;
    }

    AudioSegment& segment = *audioSegments.AppendElement();
    GraphTime next;
    for (GraphTime t = aFrom; t < aTo; t = next) {
      MediaInputPort::InputInterval interval = mInputs[0]->GetNextInputInterval(t);
      interval.mEnd = std::min(interval.mEnd, aTo);
      if (interval.mStart >= interval.mEnd)
        break;
      next = interval.mEnd;

      StreamTime outputStart = GraphTimeToStreamTime(interval.mStart);
      StreamTime outputEnd = GraphTimeToStreamTime(interval.mEnd);
      StreamTime ticks = outputEnd - outputStart;

      if (interval.mInputIsBlocked) {
        segment.AppendNullData(ticks);
      } else {
        StreamTime inputStart =
          std::min(inputSegment.GetDuration(),
                   source->GraphTimeToStreamTime(interval.mStart));
        StreamTime inputEnd =
          std::min(inputSegment.GetDuration(),
                   source->GraphTimeToStreamTime(interval.mEnd));

        segment.AppendSlice(inputSegment, inputStart, inputEnd);
        // Pad if we're looking past the end of the track
        segment.AppendNullData(ticks - (inputEnd - inputStart));
      }
    }

    for (AudioSegment::ChunkIterator iter(segment); !iter.IsEnded(); iter.Next()) {
      inputChannels = GetAudioChannelsSuperset(inputChannels, iter->ChannelCount());
    }
  }

  uint32_t accumulateIndex = 0;
  if (inputChannels) {
    nsAutoTArray<float,GUESS_AUDIO_CHANNELS*WEBAUDIO_BLOCK_SIZE> downmixBuffer;
    for (uint32_t i = 0; i < audioSegments.Length(); ++i) {
      AudioChunk tmpChunk;
      ConvertSegmentToAudioBlock(&audioSegments[i], &tmpChunk, inputChannels);
      if (!tmpChunk.IsNull()) {
        if (accumulateIndex == 0) {
          AllocateAudioBlock(inputChannels, &mLastChunks[0]);
        }
        AccumulateInputChunk(accumulateIndex, tmpChunk, &mLastChunks[0], &downmixBuffer);
        accumulateIndex++;
      }
    }
  }
  if (accumulateIndex == 0) {
    mLastChunks[0].SetNull(WEBAUDIO_BLOCK_SIZE);
  }

  // Using AudioNodeStream's AdvanceOutputSegment to push the media stream graph along with null data.
  AdvanceOutputSegment();
}

void
AudioNodeExternalInputStream::ProcessInput(GraphTime aFrom, GraphTime aTo,
                                           uint32_t aFlags)
{
  // According to spec, number of outputs is always 1.
  MOZ_ASSERT(mLastChunks.Length() == 1);

  // GC stuff can result in our input stream being destroyed before this stream.
  // Handle that.
  if (!IsEnabled() || mInputs.IsEmpty() || mPassThrough) {
    mLastChunks[0].SetNull(WEBAUDIO_BLOCK_SIZE);
    return;
  }

  MOZ_ASSERT(mInputs.Length() == 1);

  MediaStream* source = mInputs[0]->GetSource();
  AutoTArray<AudioSegment,1> audioSegments;
  uint32_t inputChannels = 0;
  for (StreamTracks::TrackIter tracks(source->mTracks);
       !tracks.IsEnded(); tracks.Next()) {
    const StreamTracks::Track& inputTrack = *tracks;
    if (!mInputs[0]->PassTrackThrough(tracks->GetID())) {
      continue;
    }

    if (inputTrack.GetSegment()->GetType() == MediaSegment::VIDEO) {
      MOZ_ASSERT(false, "AudioNodeExternalInputStream shouldn't have video tracks");
      continue;
    }

    const AudioSegment& inputSegment =
        *static_cast<AudioSegment*>(inputTrack.GetSegment());
    if (inputSegment.IsNull()) {
      continue;
    }

    AudioSegment& segment = *audioSegments.AppendElement();
    GraphTime next;
    for (GraphTime t = aFrom; t < aTo; t = next) {
      MediaInputPort::InputInterval interval = mInputs[0]->GetNextInputInterval(t);
      interval.mEnd = std::min(interval.mEnd, aTo);
      if (interval.mStart >= interval.mEnd)
        break;
      next = interval.mEnd;

      // We know this stream does not block during the processing interval ---
      // we're not finished, we don't underrun, and we're not suspended.
      StreamTime outputStart = GraphTimeToStreamTime(interval.mStart);
      StreamTime outputEnd = GraphTimeToStreamTime(interval.mEnd);
      StreamTime ticks = outputEnd - outputStart;

      if (interval.mInputIsBlocked) {
        segment.AppendNullData(ticks);
      } else {
        // The input stream is not blocked in this interval, so no need to call
        // GraphTimeToStreamTimeWithBlocking.
        StreamTime inputStart =
          std::min(inputSegment.GetDuration(),
                   source->GraphTimeToStreamTime(interval.mStart));
        StreamTime inputEnd =
          std::min(inputSegment.GetDuration(),
                   source->GraphTimeToStreamTime(interval.mEnd));

        segment.AppendSlice(inputSegment, inputStart, inputEnd);
        // Pad if we're looking past the end of the track
        segment.AppendNullData(ticks - (inputEnd - inputStart));
      }
    }

    for (AudioSegment::ChunkIterator iter(segment); !iter.IsEnded(); iter.Next()) {
      inputChannels = GetAudioChannelsSuperset(inputChannels, iter->ChannelCount());
    }
  }

  uint32_t accumulateIndex = 0;
  if (inputChannels) {
    DownmixBufferType downmixBuffer;
    ASSERT_ALIGNED16(downmixBuffer.Elements());
    for (uint32_t i = 0; i < audioSegments.Length(); ++i) {
      AudioBlock tmpChunk;
      ConvertSegmentToAudioBlock(&audioSegments[i], &tmpChunk, inputChannels);
      if (!tmpChunk.IsNull()) {
        if (accumulateIndex == 0) {
          mLastChunks[0].AllocateChannels(inputChannels);
        }
        AccumulateInputChunk(accumulateIndex, tmpChunk, &mLastChunks[0], &downmixBuffer);
        accumulateIndex++;
      }
    }
  }
  if (accumulateIndex == 0) {
    mLastChunks[0].SetNull(WEBAUDIO_BLOCK_SIZE);
  }
}

void
AudioNodeExternalInputStream::ProcessInput(GraphTime aFrom, GraphTime aTo,
                                           uint32_t aFlags)
{
  // According to spec, number of outputs is always 1.
  mLastChunks.SetLength(1);

  // GC stuff can result in our input stream being destroyed before this stream.
  // Handle that.
  if (mInputs.IsEmpty()) {
    mLastChunks[0].SetNull(WEBAUDIO_BLOCK_SIZE);
    AdvanceOutputSegment();
    return;
  }

  MOZ_ASSERT(mInputs.Length() == 1);

  MediaStream* source = mInputs[0]->GetSource();
  nsAutoTArray<AudioSegment,1> audioSegments;
  nsAutoTArray<bool,1> trackMapEntriesUsed;
  uint32_t inputChannels = 0;
  for (StreamBuffer::TrackIter tracks(source->mBuffer, MediaSegment::AUDIO);
       !tracks.IsEnded(); tracks.Next()) {
    const StreamBuffer::Track& inputTrack = *tracks;
    // Create a TrackMapEntry if necessary.
    size_t trackMapIndex = GetTrackMapEntry(inputTrack, aFrom);
    // Maybe there's nothing in this track yet. If so, ignore it. (While the
    // track is only playing silence, we may not be able to determine the
    // correct number of channels to start resampling.)
    if (trackMapIndex == nsTArray<TrackMapEntry>::NoIndex) {
      continue;
    }

    while (trackMapEntriesUsed.Length() <= trackMapIndex) {
      trackMapEntriesUsed.AppendElement(false);
    }
    trackMapEntriesUsed[trackMapIndex] = true;

    TrackMapEntry* trackMap = &mTrackMap[trackMapIndex];
    AudioSegment segment;
    GraphTime next;
    TrackRate inputTrackRate = inputTrack.GetRate();
    for (GraphTime t = aFrom; t < aTo; t = next) {
      MediaInputPort::InputInterval interval = mInputs[0]->GetNextInputInterval(t);
      interval.mEnd = std::min(interval.mEnd, aTo);
      if (interval.mStart >= interval.mEnd)
        break;
      next = interval.mEnd;

      // Ticks >= startTicks and < endTicks are in the interval
      StreamTime outputEnd = GraphTimeToStreamTime(interval.mEnd);
      TrackTicks startTicks = trackMap->mSamplesPassedToResampler + segment.GetDuration();
      StreamTime outputStart = GraphTimeToStreamTime(interval.mStart);
      NS_ASSERTION(startTicks == TimeToTicksRoundUp(inputTrackRate, outputStart),
                   "Samples missing");
      TrackTicks endTicks = TimeToTicksRoundUp(inputTrackRate, outputEnd);
      TrackTicks ticks = endTicks - startTicks;

      if (interval.mInputIsBlocked) {
        segment.AppendNullData(ticks);
      } else {
        // See comments in TrackUnionStream::CopyTrackData
        StreamTime inputStart = source->GraphTimeToStreamTime(interval.mStart);
        StreamTime inputEnd = source->GraphTimeToStreamTime(interval.mEnd);
        TrackTicks inputTrackEndPoint =
            inputTrack.IsEnded() ? inputTrack.GetEnd() : TRACK_TICKS_MAX;

        if (trackMap->mEndOfLastInputIntervalInInputStream != inputStart ||
            trackMap->mEndOfLastInputIntervalInOutputStream != outputStart) {
          // Start of a new series of intervals where neither stream is blocked.
          trackMap->mEndOfConsumedInputTicks = TimeToTicksRoundDown(inputTrackRate, inputStart) - 1;
        }
        TrackTicks inputStartTicks = trackMap->mEndOfConsumedInputTicks;
        TrackTicks inputEndTicks = inputStartTicks + ticks;
        trackMap->mEndOfConsumedInputTicks = inputEndTicks;
        trackMap->mEndOfLastInputIntervalInInputStream = inputEnd;
        trackMap->mEndOfLastInputIntervalInOutputStream = outputEnd;

        if (inputStartTicks < 0) {
          // Data before the start of the track is just null.
          segment.AppendNullData(-inputStartTicks);
          inputStartTicks = 0;
        }
        if (inputEndTicks > inputStartTicks) {
          segment.AppendSlice(*inputTrack.GetSegment(),
                              std::min(inputTrackEndPoint, inputStartTicks),
                              std::min(inputTrackEndPoint, inputEndTicks));
        }
        // Pad if we're looking past the end of the track
        segment.AppendNullData(ticks - segment.GetDuration());
      }
    }

    trackMap->mSamplesPassedToResampler += segment.GetDuration();
    trackMap->ResampleInputData(&segment);

    if (trackMap->mResampledData.GetDuration() < mCurrentOutputPosition + WEBAUDIO_BLOCK_SIZE) {
      // We don't have enough data. Delay it.
      trackMap->mResampledData.InsertNullDataAtStart(
        mCurrentOutputPosition + WEBAUDIO_BLOCK_SIZE - trackMap->mResampledData.GetDuration());
//.........这里部分代码省略.........