DeviceInputTrack.h

mozilla-central/dom/media/DeviceInputTrack.h (file symbol)

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=2 et sw=2 tw=80: */

/* 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 https://mozilla.org/MPL/2.0/. */

#ifndef DOM_MEDIA_DEVICEINPUTTRACK_H_

#define DOM_MEDIA_DEVICEINPUTTRACK_H_

#include <thread>

#include "AudioDriftCorrection.h"

#include "AudioSegment.h"

#include "AudioInputSource.h"

#include "MediaTrackGraph.h"

#include "GraphDriver.h"

#include "mozilla/NotNull.h"

namespace mozilla {

class NativeInputTrack;

class NonNativeInputTrack;

// Any MediaTrack that needs the audio data from the certain device should

// inherit the this class and get the raw audio data on graph thread via

// GetInputSourceData(), after calling ConnectDeviceInput() and before

// DisconnectDeviceInput() on main thread. See more examples in

// TestAudioTrackGraph.cpp

//

// Example:

//

// class RawAudioDataTrack : public DeviceInputConsumerTrack {

//  public:

//   ...

//

//   void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) override

//   {

//     if (aFrom >= aTo) {

//       return;

//     }

//

//     if (mInputs.IsEmpty()) {

//       GetData<AudioSegment>()->AppendNullData(aTo - aFrom);

//     } else {

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

//       AudioSegment data;

//       DeviceInputConsumerTrack::GetInputSourceData(data, aFrom, aTo);

//       // You can do audio data processing before appending to mSegment here.

//       GetData<AudioSegment>()->AppendFrom(&data);

//     }

//   };

//

//   uint32_t NumberOfChannels() const override {

//     if (mInputs.IsEmpty()) {

//       return 0;

//     }

//     DeviceInputTrack* t = mInputs[0]->GetSource()->AsDeviceInputTrack();

//     MOZ_ASSERT(t);

//     return t->NumberOfChannels();

//   }

//

//   ...

//

//  private:

//   explicit RawAudioDataTrack(TrackRate aSampleRate)

//       : DeviceInputConsumerTrack(aSampleRate) {}

// };

class DeviceInputConsumerTrack : public ProcessedMediaTrack {

 public:

  explicit DeviceInputConsumerTrack(TrackRate aSampleRate);

  // Main Thread APIs:

  void ConnectDeviceInput(CubebUtils::AudioDeviceID aId,

                          AudioDataListener* aListener,

                          const PrincipalHandle& aPrincipal);

  void DisconnectDeviceInput();

  Maybe<CubebUtils::AudioDeviceID> DeviceId() const;

  NotNull<AudioDataListener*> GetAudioDataListener() const;

  bool ConnectedToNativeDevice() const;

  bool ConnectedToNonNativeDevice() const;

  // Any thread:

  DeviceInputConsumerTrack* AsDeviceInputConsumerTrack() override {

    return this;

  // Graph thread API:

  DeviceInputTrack* GetDeviceInputTrackGraphThread() const;

 protected:

  // Get the data in [aFrom, aTo) from the device input to aOutput. aOutput

  // needs to be empty. A device input must be connected. Graph thread.

  void GetInputSourceData(AudioSegment& aOutput, GraphTime aFrom,

                          GraphTime aTo) const;

  // Main Thread variables:

  RefPtr<MediaInputPort> mPort;

  RefPtr<DeviceInputTrack> mDeviceInputTrack;

  RefPtr<AudioDataListener> mListener;

  Maybe<CubebUtils::AudioDeviceID> mDeviceId;

};

class DeviceInputTrack : public ProcessedMediaTrack {

 public:

  // Main Thread APIs:

  // Any MediaTrack that needs the audio data from the certain device should

  // inherit the DeviceInputConsumerTrack class and call GetInputSourceData to

  // get the data instead of using the below APIs.

//

  // The following two APIs can create and destroy a DeviceInputTrack reference

  // on main thread, then open and close the underlying audio device accordingly

  // on the graph thread. The user who wants to read the audio input from a

  // certain device should use these APIs to obtain a DeviceInputTrack reference

  // and release the reference when the user no longer needs the audio data.

//

  // Once the DeviceInputTrack is created on the main thread, the paired device

  // will start producing data, so its users can read the data immediately on

  // the graph thread, once they obtain the reference. The lifetime of

  // DeviceInputTrack is managed by the MediaTrackGraph itself. When the

  // DeviceInputTrack has no user any more, MediaTrackGraph will destroy it.

  // This means, it occurs when the last reference has been released by the API

  // below.

//

  // The DeviceInputTrack is either a NativeInputTrack, or a

  // NonNativeInputTrack. We can have only one NativeInputTrack per

  // MediaTrackGraph, but multiple NonNativeInputTrack per graph. The audio

  // device paired with the NativeInputTrack is called "native device", and the

  // device paired with the NonNativeInputTrack is called "non-native device".

  // In other words, we can have only one native device per MediaTrackGraph, but

  // many non-native devices per graph.

//

  // The native device is the first input device created in the MediaTrackGraph.

  // All other devices created after it will be non-native devices. Once the

  // native device is destroyed, the first non-native device will be promoted to

  // the new native device. The switch will be started by the MediaTrackGraph.

  // The MediaTrackGraph will force DeviceInputTrack's users to re-configure

  // their DeviceInputTrack connections with the APIs below to execute the

  // switching.

//

  // The native device is also the audio input device serving the

  // AudioCallbackDriver, which drives the MediaTrackGraph periodically from

  // audio callback thread. The audio data produced by the native device and

  // non-native device is stored in NativeInputTrack and NonNativeInputTrack

  // respectively, and then accessed by their users. The only difference between

  // these audio data is that the data from the non-native device is

  // clock-drift-corrected since the non-native device may run on a different

  // clock than the native device's one.

//

  // Example:

  //   // On main thread

  //   RefPtr<DeviceInputTrack> track = DeviceInputTrack::OpenAudio(...);

  //   ...

  //   // On graph thread

  //   AudioSegmen* data = track->GetData<AudioSegment>();

  //   ...

  //   // On main thread

  //   DeviceInputTrack::CloseAudio(track.forget(), ...);

//

  // Returns a reference of DeviceInputTrack, storing the input audio data from

  // the given device, in the given MediaTrackGraph. The paired audio device

  // will be opened accordingly. The DeviceInputTrack will access its user's

  // audio settings via the attached AudioDataListener, and delivers the

  // notifications when it needs.

  static NotNull<RefPtr<DeviceInputTrack>> OpenAudio(

      MediaTrackGraph* aGraph, CubebUtils::AudioDeviceID aDeviceId,

      const PrincipalHandle& aPrincipalHandle,

      DeviceInputConsumerTrack* aConsumer);

  // Destroy the DeviceInputTrack reference obtained by the above API. The

  // paired audio device will be closed accordingly.

  static void CloseAudio(already_AddRefed<DeviceInputTrack> aTrack,

                         DeviceInputConsumerTrack* aConsumer);

  // Main thread API:

  const nsTArray<RefPtr<DeviceInputConsumerTrack>>& GetConsumerTracks() const;

  // Graph thread APIs:

  // Query audio settings from its users.

  uint32_t MaxRequestedInputChannels() const;

  bool HasVoiceInput() const;

  // Deliver notification to its users.

  void DeviceChanged(MediaTrackGraph* aGraph) const;

  // Any thread:

  DeviceInputTrack* AsDeviceInputTrack() override { return this; }

  virtual NativeInputTrack* AsNativeInputTrack() { return nullptr; }

  virtual NonNativeInputTrack* AsNonNativeInputTrack() { return nullptr; }

  // Any thread:

  const CubebUtils::AudioDeviceID mDeviceId;

  const PrincipalHandle mPrincipalHandle;

 protected:

  DeviceInputTrack(TrackRate aSampleRate, CubebUtils::AudioDeviceID aDeviceId,

                   const PrincipalHandle& aPrincipalHandle);

  ~DeviceInputTrack() = default;

 private:

  // Main thread APIs:

  void ReevaluateInputDevice();

  void AddDataListener(AudioDataListener* aListener);

  void RemoveDataListener(AudioDataListener* aListener);

  // Only accessed on the main thread.

  // When this becomes empty, this DeviceInputTrack is no longer needed.

  nsTArray<RefPtr<DeviceInputConsumerTrack>> mConsumerTracks;

  // Only accessed on the graph thread.

  nsTArray<RefPtr<AudioDataListener>> mListeners;

};

class NativeInputTrack final : public DeviceInputTrack {

 public:

  // Do not call this directly. This can only be called in DeviceInputTrack or

  // tests.

  NativeInputTrack(TrackRate aSampleRate, CubebUtils::AudioDeviceID aDeviceId,

                   const PrincipalHandle& aPrincipalHandle);

  // Graph Thread APIs, for ProcessedMediaTrack.

  void DestroyImpl() override;

  void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) override;

  uint32_t NumberOfChannels() const override;

  // Graph thread APIs: Get input audio data and event from graph.

  void NotifyInputStopped(MediaTrackGraph* aGraph);

  void NotifyInputData(MediaTrackGraph* aGraph, const AudioDataValue* aBuffer,

                       size_t aFrames, TrackRate aRate, uint32_t aChannels,

                       uint32_t aAlreadyBuffered);

  // Any thread

  NativeInputTrack* AsNativeInputTrack() override { return this; }

 private:

  ~NativeInputTrack() = default;

  // Graph thread only members:

  // Indicate whether we append extra frames in mPendingData. The extra number

  // of frames is in [0, WEBAUDIO_BLOCK_SIZE] range.

  bool mIsBufferingAppended = false;

  // Queue the audio input data coming from NotifyInputData.

  AudioSegment mPendingData;

  // The input channel count for the audio data.

  uint32_t mInputChannels = 0;

};

class NonNativeInputTrack final : public DeviceInputTrack {

 public:

  // Do not call this directly. This can only be called in DeviceInputTrack or

  // tests.

  NonNativeInputTrack(TrackRate aSampleRate,

                      CubebUtils::AudioDeviceID aDeviceId,

                      const PrincipalHandle& aPrincipalHandle);

  // Graph Thread APIs, for ProcessedMediaTrack

  void DestroyImpl() override;

  void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) override;

  uint32_t NumberOfChannels() const override;

  // Any thread

  NonNativeInputTrack* AsNonNativeInputTrack() override { return this; }

  // Graph thread APIs:

  void StartAudio(RefPtr<AudioInputSource>&& aAudioInputSource);

  void StopAudio();

  AudioInputType DevicePreference() const;

  void NotifyDeviceChanged(AudioInputSource::Id aSourceId);

  void NotifyInputStopped(AudioInputSource::Id aSourceId);

  AudioInputSource::Id GenerateSourceId();

 private:

  ~NonNativeInputTrack() = default;

  // Graph thread only.

  RefPtr<AudioInputSource> mAudioSource;

  AudioInputSource::Id mSourceIdNumber;

#ifdef DEBUG

  // Graph thread only.

  bool HasGraphThreadChanged();

  // Graph thread only.  Identifies a thread only between StartAudio()

  // and StopAudio(), to track the thread used with mAudioSource.

  std::thread::id mGraphThreadId;

#endif

};

class AudioInputSourceListener : public AudioInputSource::EventListener {

 public:

  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AudioInputSourceListener, override);

  explicit AudioInputSourceListener(NonNativeInputTrack* aOwner);

  // Main thread APIs:

  void AudioDeviceChanged(AudioInputSource::Id aSourceId) override;

  void AudioStateCallback(

      AudioInputSource::Id aSourceId,

      AudioInputSource::EventListener::State aState) override;

 private:

  ~AudioInputSourceListener() = default;

  const RefPtr<NonNativeInputTrack> mOwner;

};

}  // namespace mozilla

#endif  // DOM_MEDIA_DEVICEINPUTTRACK_H_