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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 */
#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, mInputs[0], 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();
// return t->NumberOfChannels();
// }
// ...
// private:
// explicit RawAudioDataTrack(TrackRate aSampleRate)
// : DeviceInputConsumerTrack(aSampleRate) {}
// };
class DeviceInputConsumerTrack : public ProcessedMediaTrack {
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;
// Any thread:
bool ConnectToNativeDevice() const;
bool ConnectToNonNativeDevice() const;
DeviceInputConsumerTrack* AsDeviceInputConsumerTrack() override {
return this;
// Graph thread API:
// Get the data in [aFrom, aTo) from aPort->GetSource() to aOutput. aOutput
// needs to be empty.
void GetInputSourceData(AudioSegment& aOutput, const MediaInputPort* aPort,
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 {
// 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(
MediaTrackGraphImpl* 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(MediaTrackGraphImpl* 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;
DeviceInputTrack(TrackRate aSampleRate, CubebUtils::AudioDeviceID aDeviceId,
const PrincipalHandle& aPrincipalHandle);
~DeviceInputTrack() = default;
// 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 {
// 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(MediaTrackGraphImpl* aGraph);
void NotifyInputData(MediaTrackGraphImpl* aGraph,
const AudioDataValue* aBuffer, size_t aFrames,
TrackRate aRate, uint32_t aChannels,
uint32_t aAlreadyBuffered);
// Any thread
NativeInputTrack* AsNativeInputTrack() override { return this; }
~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 {
// 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();
~NonNativeInputTrack() = default;
// Graph driver thread only.
bool CheckGraphDriverChanged();
// Graph thread only.
RefPtr<AudioInputSource> mAudioSource;
AudioInputSource::Id mSourceIdNumber;
// Graph driver thread only.
std::thread::id mGraphDriverThreadId;
class AudioInputSourceListener : public AudioInputSource::EventListener {
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;
~AudioInputSourceListener() = default;
const RefPtr<NonNativeInputTrack> mOwner;
} // namespace mozilla