dom/media/CrossGraphPort.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   4  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef MOZILLA_CROSS_GRAPH_TRACK_H_
   7 #define MOZILLA_CROSS_GRAPH_TRACK_H_
   8
   9 #include "AudioDriftCorrection.h"
  10 #include "AudioSegment.h"
  11 #include "ForwardedInputTrack.h"
  12 #include "mozilla/SPSCQueue.h"
  13 #include "mozilla/UniquePtr.h"
  14
  15 namespace mozilla {
  16 class CrossGraphReceiver;
  17 }
  18
  19 namespace mozilla::dom {
  20 class AudioStreamTrack;
  21 }
  22
  23 namespace mozilla {
  24
  25 /**
  26  * See MediaTrackGraph::CreateCrossGraphTransmitter()
  27  */
  28 class CrossGraphTransmitter : public ProcessedMediaTrack {
  29  public:
  30   CrossGraphTransmitter(TrackRate aSampleRate,
  31                         RefPtr<CrossGraphReceiver> aReceiver);
  32   CrossGraphTransmitter* AsCrossGraphTransmitter() override { return this; }
  33
  34   uint32_t NumberOfChannels() const override {
  35     MOZ_CRASH("CrossGraphTransmitter has no segment. It cannot be played out.");
  36   }
  37   void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) override;
  38
  39  private:
  40   const RefPtr<CrossGraphReceiver> mReceiver;
  41 };
  42
  43 /**
  44  * See MediaTrackGraph::CreateCrossGraphReceiver()
  45  */
  46 class CrossGraphReceiver : public ProcessedMediaTrack {
  47  public:
  48   CrossGraphReceiver(TrackRate aSampleRate, TrackRate aTransmitterRate);
  49   CrossGraphReceiver* AsCrossGraphReceiver() override { return this; }
  50
  51   uint32_t NumberOfChannels() const override;
  52   void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) override;
  53
  54   int EnqueueAudio(AudioChunk& aChunk);
  55
  56  private:
  57   SPSCQueue<AudioChunk> mCrossThreadFIFO{30};
  58   // Indicates that tre CrossGraphTransmitter has started sending frames. It
  59   // is false untill the point, transmitter has sent the first valid frame.
  60   // Accessed in GraphThread only.
  61   bool mTransmitterHasStarted = false;
  62   // Correct the drift between transmitter and receiver. Reciever (this class)
  63   // is considered as the master clock.
  64   // Accessed in GraphThread only.
  65   AudioDriftCorrection mDriftCorrection;
  66 };
  67
  68 class CrossGraphPort final {
  69  public:
  70   static UniquePtr<CrossGraphPort> Connect(
  71       const RefPtr<dom::AudioStreamTrack>& aStreamTrack,
  72       MediaTrackGraph* aPartnerGraph);
  73   static UniquePtr<CrossGraphPort> Connect(
  74       const RefPtr<dom::AudioStreamTrack>& aStreamTrack, AudioDeviceInfo* aSink,
  75       nsPIDOMWindowInner* aWindow);
  76   ~CrossGraphPort();
  77
  78   void AddAudioOutput(void* aKey);
  79   void RemoveAudioOutput(void* aKey);
  80   void SetAudioOutputVolume(void* aKey, float aVolume);
  81
  82   RefPtr<GenericPromise> EnsureConnected();
  83
  84   const RefPtr<CrossGraphTransmitter> mTransmitter;
  85   const RefPtr<CrossGraphReceiver> mReceiver;
  86
  87  private:
  88   explicit CrossGraphPort(RefPtr<MediaInputPort> aTransmitterPort,
  89                           RefPtr<CrossGraphTransmitter> aTransmitter,
  90                           RefPtr<CrossGraphReceiver> aReceiver)
  91       : mTransmitter(std::move(aTransmitter)),
  92         mReceiver(std::move(aReceiver)),
  93         mTransmitterPort(std::move(aTransmitterPort)) {
  94     MOZ_ASSERT(mTransmitter);
  95     MOZ_ASSERT(mReceiver);
  96     MOZ_ASSERT(mTransmitterPort);
  97   }
  98
  99   // The port that connects the input track to the transmitter.
 100   const RefPtr<MediaInputPort> mTransmitterPort;
 101 };
 102
 103 }  // namespace mozilla
 104
 105 #endif /* MOZILLA_CROSS_GRAPH_TRACK_H_ */