components/audio_modem/audio_player_impl.cc

   1 // Copyright 2015 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/audio_modem/audio_player_impl.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/audio_modem/public/audio_modem_types.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 audio_modem {
  28
  29 // Public methods.
  30
  31 AudioPlayerImpl::AudioPlayerImpl()
  32     : is_playing_(false), stream_(nullptr), frame_index_(0) {
  33 }
  34
  35 AudioPlayerImpl::~AudioPlayerImpl() {
  36 }
  37
  38 void AudioPlayerImpl::Initialize() {
  39   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  40       FROM_HERE,
  41       base::Bind(&AudioPlayerImpl::InitializeOnAudioThread,
  42                  base::Unretained(this)));
  43 }
  44
  45 void AudioPlayerImpl::Play(
  46     const scoped_refptr<media::AudioBusRefCounted>& samples) {
  47   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  48       FROM_HERE,
  49       base::Bind(&AudioPlayerImpl::PlayOnAudioThread,
  50                  base::Unretained(this),
  51                  samples));
  52 }
  53
  54 void AudioPlayerImpl::Stop() {
  55   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  56       FROM_HERE,
  57       base::Bind(&AudioPlayerImpl::StopOnAudioThread, base::Unretained(this)));
  58 }
  59
  60 void AudioPlayerImpl::Finalize() {
  61   media::AudioManager::Get()->GetTaskRunner()->PostTask(
  62       FROM_HERE,
  63       base::Bind(&AudioPlayerImpl::FinalizeOnAudioThread,
  64                  base::Unretained(this)));
  65 }
  66
  67 // Private methods.
  68
  69 void AudioPlayerImpl::InitializeOnAudioThread() {
  70   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
  71   stream_ = output_stream_for_testing_
  72                 ? output_stream_for_testing_.get()
  73                 : media::AudioManager::Get()->MakeAudioOutputStreamProxy(
  74                       media::AudioParameters(
  75                           media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
  76                           media::CHANNEL_LAYOUT_MONO,
  77                           kDefaultSampleRate,
  78                           kDefaultBitsPerSample,
  79                           kDefaultFrameCount),
  80                       std::string());
  81
  82   if (!stream_ || !stream_->Open()) {
  83     LOG(ERROR) << "Failed to open an output stream.";
  84     if (stream_) {
  85       stream_->Close();
  86       stream_ = nullptr;
  87     }
  88     return;
  89   }
  90   stream_->SetVolume(kOutputVolumePercent);
  91 }
  92
  93 void AudioPlayerImpl::PlayOnAudioThread(
  94     const scoped_refptr<media::AudioBusRefCounted>& samples) {
  95   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
  96   if (!stream_ || is_playing_)
  97     return;
  98
  99   {
 100     base::AutoLock al(state_lock_);
 101     samples_ = samples;
 102     frame_index_ = 0;
 103   }
 104
 105   VLOG(3) << "Starting playback.";
 106   is_playing_ = true;
 107   stream_->Start(this);
 108 }
 109
 110 void AudioPlayerImpl::StopOnAudioThread() {
 111   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
 112   if (!stream_ || !is_playing_)
 113     return;
 114
 115   VLOG(3) << "Stopping playback.";
 116   stream_->Stop();
 117   is_playing_ = false;
 118 }
 119
 120 void AudioPlayerImpl::StopAndCloseOnAudioThread() {
 121   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
 122   if (!stream_)
 123     return;
 124
 125   StopOnAudioThread();
 126   stream_->Close();
 127   stream_ = nullptr;
 128 }
 129
 130 void AudioPlayerImpl::FinalizeOnAudioThread() {
 131   DCHECK(media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread());
 132   StopAndCloseOnAudioThread();
 133   delete this;
 134 }
 135
 136 int AudioPlayerImpl::OnMoreData(media::AudioBus* dest,
 137                                 uint32 /* total_bytes_delay */) {
 138   base::AutoLock al(state_lock_);
 139   // Continuously play our samples till explicitly told to stop.
 140   const int leftover_frames = samples_->frames() - frame_index_;
 141   const int frames_to_copy = std::min(dest->frames(), leftover_frames);
 142
 143   samples_->CopyPartialFramesTo(frame_index_, frames_to_copy, 0, dest);
 144   frame_index_ += frames_to_copy;
 145
 146   // If we didn't fill the destination audio bus, wrap around and fill the rest.
 147   if (leftover_frames <= dest->frames()) {
 148     samples_->CopyPartialFramesTo(
 149         0, dest->frames() - frames_to_copy, frames_to_copy, dest);
 150     frame_index_ = dest->frames() - frames_to_copy;
 151   }
 152
 153   return dest->frames();
 154 }
 155
 156 void AudioPlayerImpl::OnError(media::AudioOutputStream* /* stream */) {
 157   LOG(ERROR) << "Error during system sound reproduction.";
 158   media::AudioManager::Get()->GetTaskRunner()->PostTask(
 159       FROM_HERE,
 160       base::Bind(&AudioPlayerImpl::StopAndCloseOnAudioThread,
 161                  base::Unretained(this)));
 162 }
 163
 164 void AudioPlayerImpl::FlushAudioLoopForTesting() {
 165   if (media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread())
 166     return;
 167
 168   // Queue task on the audio thread, when it is executed, that means we've
 169   // successfully executed all the tasks before us.
 170   base::RunLoop rl;
 171   media::AudioManager::Get()->GetTaskRunner()->PostTaskAndReply(
 172       FROM_HERE,
 173       base::Bind(base::IgnoreResult(&AudioPlayerImpl::FlushAudioLoopForTesting),
 174                  base::Unretained(this)),
 175       rl.QuitClosure());
 176   rl.Run();
 177 }
 178
 179 }  // namespace audio_modem