media/audio/audio_output_stream_sink.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/audio/audio_output_stream_sink.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/location.h"
  10 #include "media/audio/audio_manager.h"
  11
  12 namespace media {
  13
  14 AudioOutputStreamSink::AudioOutputStreamSink()
  15     : render_callback_(NULL),
  16       audio_task_runner_(AudioManager::Get()->GetTaskRunner()),
  17       stream_(NULL),
  18       active_render_callback_(NULL) {
  19 }
  20
  21 AudioOutputStreamSink::~AudioOutputStreamSink() {
  22 }
  23
  24 void AudioOutputStreamSink::Initialize(const AudioParameters& params,
  25                                        RenderCallback* callback) {
  26   DCHECK(callback);
  27   DCHECK(!render_callback_);
  28   params_ = params;
  29   render_callback_ = callback;
  30 }
  31
  32 void AudioOutputStreamSink::Start() {
  33   audio_task_runner_->PostTask(
  34       FROM_HERE, base::Bind(&AudioOutputStreamSink::DoStart, this));
  35 }
  36
  37 void AudioOutputStreamSink::Stop() {
  38   ClearCallback();
  39   audio_task_runner_->PostTask(
  40       FROM_HERE, base::Bind(&AudioOutputStreamSink::DoStop, this));
  41 }
  42
  43 void AudioOutputStreamSink::Pause() {
  44   ClearCallback();
  45   audio_task_runner_->PostTask(
  46       FROM_HERE, base::Bind(&AudioOutputStreamSink::DoPause, this));
  47 }
  48
  49 void AudioOutputStreamSink::Play() {
  50   base::AutoLock al(callback_lock_);
  51   active_render_callback_ = render_callback_;
  52   audio_task_runner_->PostTask(
  53       FROM_HERE, base::Bind(&AudioOutputStreamSink::DoPlay, this));
  54 }
  55
  56 bool AudioOutputStreamSink::SetVolume(double volume) {
  57   audio_task_runner_->PostTask(
  58       FROM_HERE, base::Bind(&AudioOutputStreamSink::DoSetVolume, this, volume));
  59   return true;
  60 }
  61
  62 OutputDevice* AudioOutputStreamSink::GetOutputDevice() {
  63   return nullptr;
  64 }
  65
  66 int AudioOutputStreamSink::OnMoreData(AudioBus* dest,
  67                                       uint32 total_bytes_delay) {
  68   // Note: Runs on the audio thread created by the OS.
  69   base::AutoLock al(callback_lock_);
  70   if (!active_render_callback_)
  71     return 0;
  72
  73   return active_render_callback_->Render(
  74       dest, total_bytes_delay * 1000.0 / params_.GetBytesPerSecond());
  75 }
  76
  77 void AudioOutputStreamSink::OnError(AudioOutputStream* stream) {
  78   // Note: Runs on the audio thread created by the OS.
  79   base::AutoLock al(callback_lock_);
  80   if (active_render_callback_)
  81     active_render_callback_->OnRenderError();
  82 }
  83
  84 void AudioOutputStreamSink::DoStart() {
  85   DCHECK(audio_task_runner_->BelongsToCurrentThread());
  86
  87   // Create an AudioOutputStreamProxy which will handle any and all resampling
  88   // necessary to generate a low latency output stream.
  89   stream_ =
  90       AudioManager::Get()->MakeAudioOutputStreamProxy(params_, std::string());
  91   if (!stream_ || !stream_->Open()) {
  92     render_callback_->OnRenderError();
  93     if (stream_)
  94       stream_->Close();
  95     stream_ = NULL;
  96   }
  97 }
  98
  99 void AudioOutputStreamSink::DoStop() {
 100   DCHECK(audio_task_runner_->BelongsToCurrentThread());
 101
 102   if (!stream_)
 103     return;
 104
 105   DoPause();
 106   stream_->Close();
 107   stream_ = NULL;
 108 }
 109
 110 void AudioOutputStreamSink::DoPause() {
 111   DCHECK(audio_task_runner_->BelongsToCurrentThread());
 112   stream_->Stop();
 113 }
 114
 115 void AudioOutputStreamSink::DoPlay() {
 116   DCHECK(audio_task_runner_->BelongsToCurrentThread());
 117   stream_->Start(this);
 118 }
 119
 120 void AudioOutputStreamSink::DoSetVolume(double volume) {
 121   DCHECK(audio_task_runner_->BelongsToCurrentThread());
 122   stream_->SetVolume(volume);
 123 }
 124
 125 void AudioOutputStreamSink::ClearCallback() {
 126   base::AutoLock al(callback_lock_);
 127   active_render_callback_ = NULL;
 128 }
 129
 130 }  // namepace media