/* -*- 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, * You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "MediaTrackGraphImpl.h" #include "MediaTrackListener.h" #include "mozilla/MathAlgorithms.h" #include "mozilla/Unused.h" #include "AudioSegment.h" #include "mozilla/Logging.h" #include "mozilla/Attributes.h" #include "AudioCaptureTrack.h" #include "ImageContainer.h" #include "AudioNodeEngine.h" #include "AudioNodeTrack.h" #include "AudioNodeExternalInputTrack.h" #include "webaudio/MediaStreamAudioDestinationNode.h" #include <algorithm> #include "DOMMediaStream.h" using namespace mozilla::layers; using namespace mozilla::dom; using namespace mozilla::gfx; namespace mozilla { // We are mixing to mono until PeerConnection can accept stereo static const uint32_t MONO = 1; AudioCaptureTrack::AudioCaptureTrack(TrackRate aRate) : ProcessedMediaTrack(aRate, MediaSegment::AUDIO, new AudioSegment()), mStarted(false) { MOZ_ASSERT(NS_IsMainThread()); MOZ_COUNT_CTOR(AudioCaptureTrack); mMixer.AddCallback(WrapNotNull(this)); } AudioCaptureTrack::~AudioCaptureTrack() { MOZ_COUNT_DTOR(AudioCaptureTrack); mMixer.RemoveCallback(this); } void AudioCaptureTrack::Start() { class Message : public ControlMessage { public: explicit Message(AudioCaptureTrack* aTrack) : ControlMessage(aTrack), mTrack(aTrack) {} virtual void Run() { mTrack->mStarted = true; } protected: AudioCaptureTrack* mTrack; }; GraphImpl()->AppendMessage(MakeUnique<Message>(this)); } void AudioCaptureTrack::ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) { if (!mStarted) { return; } uint32_t inputCount = mInputs.Length(); if (mEnded) { return; } // If the captured track is connected back to a object on the page (be it an // HTMLMediaElement with a track as source, or an AudioContext), a cycle // situation occur. This can work if it's an AudioContext with at least one // DelayNode, but the MTG will mute the whole cycle otherwise. if (InMutedCycle() || inputCount == 0) { GetData<AudioSegment>()->AppendNullData(aTo - aFrom); } else { // We mix down all the tracks of all inputs, to a stereo track. Everything // is {up,down}-mixed to stereo. mMixer.StartMixing(); AudioSegment output; for (uint32_t i = 0; i < inputCount; i++) { MediaTrack* s = mInputs[i]->GetSource(); AudioSegment* inputSegment = s->GetData<AudioSegment>(); TrackTime inputStart = s->GraphTimeToTrackTimeWithBlocking(aFrom); TrackTime inputEnd = s->GraphTimeToTrackTimeWithBlocking(aTo); AudioSegment toMix; if (s->Ended() && inputSegment->GetDuration() <= inputStart) { toMix.AppendNullData(aTo - aFrom); } else { toMix.AppendSlice(*inputSegment, inputStart, inputEnd); // Care for tracks blocked in the [aTo, aFrom] range. if (inputEnd - inputStart < aTo - aFrom) { toMix.AppendNullData((aTo - aFrom) - (inputEnd - inputStart)); } } toMix.Mix(mMixer, MONO, Graph()->GraphRate()); } // This calls MixerCallback below mMixer.FinishMixing(); } } uint32_t AudioCaptureTrack::NumberOfChannels() const { return GetData<AudioSegment>()->MaxChannelCount(); } void AudioCaptureTrack::MixerCallback(AudioDataValue* aMixedBuffer, AudioSampleFormat aFormat, uint32_t aChannels, uint32_t aFrames, uint32_t aSampleRate) { AutoTArray<nsTArray<AudioDataValue>, MONO> output; AutoTArray<const AudioDataValue*, MONO> bufferPtrs; output.SetLength(MONO); bufferPtrs.SetLength(MONO); uint32_t written = 0; // We need to copy here, because the mixer will reuse the storage, we should // not hold onto it. Buffers are in planar format. for (uint32_t channel = 0; channel < aChannels; channel++) { AudioDataValue* out = output[channel].AppendElements(aFrames); PodCopy(out, aMixedBuffer + written, aFrames); bufferPtrs[channel] = out; written += aFrames; } AudioChunk chunk; chunk.mBuffer = new mozilla::SharedChannelArrayBuffer<AudioDataValue>(std::move(output)); chunk.mDuration = aFrames; chunk.mBufferFormat = aFormat; chunk.mChannelData.SetLength(MONO); for (uint32_t channel = 0; channel < aChannels; channel++) { chunk.mChannelData[channel] = bufferPtrs[channel]; } // Now we have mixed data, simply append it. GetData<AudioSegment>()->AppendAndConsumeChunk(&chunk); } } // namespace mozilla