src/components/copresence/mediums/audio/audio_player.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 "components/copresence/mediums/audio/audio_player.h"
   6
   7 #include <algorithm>
   8 #include <string>
   9
  10 #include "base/bind.h"
  11 #include "base/bind_helpers.h"
  12 #include "base/logging.h"
  13 #include "base/run_loop.h"
  14 #include "components/copresence/public/copresence_constants.h"
  15 #include "content/public/browser/browser_thread.h"
  16 #include "media/audio/audio_manager.h"
  17 #include "media/audio/audio_parameters.h"
  18 #include "media/base/audio_bus.h"
  19
  20 namespace {
  21
  22 const int kDefaultFrameCount = 1024;
  23 const double kOutputVolumePercent = 1.0f;
  24
  25 }  // namespace
  26
  27 namespace copresence {
  28
  29 // Public methods.
  30
  31 AudioPlayer::AudioPlayer()
  32     : is_playing_(false), stream_(NULL), frame_index_(0) {
  33 }
  34
  35 AudioPlayer::~AudioPlayer() {
  36 }
  37
  38 void AudioPlayer::Initialize() {
  39   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  40       FROM_HERE,
  41       base::Bind(&AudioPlayer::InitializeOnAudioThread,
  42                  base::Unretained(this)));
  43 }
  44
  45 void AudioPlayer::Play(
  46     const scoped_refptr<media::AudioBusRefCounted>& samples) {
  47   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  48       FROM_HERE,
  49       base::Bind(
  50           &AudioPlayer::PlayOnAudioThread, base::Unretained(this), samples));
  51 }
  52
  53 void AudioPlayer::Stop() {
  54   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  55       FROM_HERE,
  56       base::Bind(&AudioPlayer::StopOnAudioThread, base::Unretained(this)));
  57 }
  58
  59 bool AudioPlayer::IsPlaying() {
  60   return is_playing_;
  61 }
  62
  63 void AudioPlayer::Finalize() {
  64   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  65       FROM_HERE,
  66       base::Bind(&AudioPlayer::FinalizeOnAudioThread, base::Unretained(this)));
  67 }
  68
  69 // Private methods.
  70
  71 void AudioPlayer::InitializeOnAudioThread() {
  72   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
  73   stream_ = output_stream_for_testing_
  74                 ? output_stream_for_testing_.get()
  75                 : media::AudioManager::Get()->MakeAudioOutputStreamProxy(
  76                       media::AudioParameters(
  77                           media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
  78                           media::CHANNEL_LAYOUT_MONO,
  79                           kDefaultSampleRate,
  80                           kDefaultBitsPerSample,
  81                           kDefaultFrameCount),
  82                       std::string());
  83
  84   if (!stream_ || !stream_->Open()) {
  85     LOG(ERROR) << "Failed to open an output stream.";
  86     if (stream_) {
  87       stream_->Close();
  88       stream_ = NULL;
  89     }
  90     return;
  91   }
  92   stream_->SetVolume(kOutputVolumePercent);
  93 }
  94
  95 void AudioPlayer::PlayOnAudioThread(
  96     const scoped_refptr<media::AudioBusRefCounted>& samples) {
  97   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
  98   if (!stream_)
  99     return;
 100
 101   {
 102     base::AutoLock al(state_lock_);
 103
 104     samples_ = samples;
 105     frame_index_ = 0;
 106
 107     if (is_playing_)
 108       return;
 109   }
 110
 111   is_playing_ = true;
 112   stream_->Start(this);
 113 }
 114
 115 void AudioPlayer::StopOnAudioThread() {
 116   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
 117   if (!stream_)
 118     return;
 119
 120   stream_->Stop();
 121   is_playing_ = false;
 122 }
 123
 124 void AudioPlayer::StopAndCloseOnAudioThread() {
 125   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
 126   if (!stream_)
 127     return;
 128
 129   if (is_playing_)
 130     stream_->Stop();
 131   stream_->Close();
 132   stream_ = NULL;
 133
 134   is_playing_ = false;
 135 }
 136
 137 void AudioPlayer::FinalizeOnAudioThread() {
 138   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
 139   StopAndCloseOnAudioThread();
 140   delete this;
 141 }
 142
 143 int AudioPlayer::OnMoreData(media::AudioBus* dest,
 144                             media::AudioBuffersState /* state */) {
 145   base::AutoLock al(state_lock_);
 146   // Continuously play our samples till explicitly told to stop.
 147   const int leftover_frames = samples_->frames() - frame_index_;
 148   const int frames_to_copy = std::min(dest->frames(), leftover_frames);
 149
 150   samples_->CopyPartialFramesTo(frame_index_, frames_to_copy, 0, dest);
 151   frame_index_ += frames_to_copy;
 152
 153   // If we didn't fill the destination audio bus, wrap around and fill the rest.
 154   if (leftover_frames <= dest->frames()) {
 155     samples_->CopyPartialFramesTo(
 156         0, dest->frames() - frames_to_copy, frames_to_copy, dest);
 157     frame_index_ = dest->frames() - frames_to_copy;
 158   }
 159
 160   return dest->frames();
 161 }
 162
 163 void AudioPlayer::OnError(media::AudioOutputStream* /* stream */) {
 164   LOG(ERROR) << "Error during system sound reproduction.";
 165   media::AudioManager::Get()->GetTaskRunner()->PostTask(
 166       FROM_HERE,
 167       base::Bind(&AudioPlayer::StopAndCloseOnAudioThread,
 168                  base::Unretained(this)));
 169 }
 170
 171 void AudioPlayer::FlushAudioLoopForTesting() {
 172   if (media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread())
 173     return;
 174
 175   // Queue task on the audio thread, when it is executed, that means we've
 176   // successfully executed all the tasks before us.
 177   base::RunLoop rl;
 178   media::AudioManager::Get()->GetTaskRunner()->PostTaskAndReply(
 179       FROM_HERE,
 180       base::Bind(base::IgnoreResult(&AudioPlayer::FlushAudioLoopForTesting),
 181                  base::Unretained(this)),
 182       rl.QuitClosure());
 183   rl.Run();
 184 }
 185
 186 }  // namespace copresence