content/renderer/media/webaudio_capturer_source.cc

   1 // Copyright (c) 2012 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 "content/renderer/media/webaudio_capturer_source.h"
   6
   7 #include "base/logging.h"
   8 #include "content/renderer/media/webrtc_audio_capturer.h"
   9
  10 using media::AudioBus;
  11 using media::AudioFifo;
  12 using media::AudioParameters;
  13 using media::ChannelLayout;
  14 using media::CHANNEL_LAYOUT_MONO;
  15 using media::CHANNEL_LAYOUT_STEREO;
  16
  17 static const int kFifoSize = 2048;
  18
  19 namespace content {
  20
  21 WebAudioCapturerSource::WebAudioCapturerSource(WebRtcAudioCapturer* capturer)
  22     : capturer_(capturer),
  23       set_format_channels_(0),
  24       callback_(0),
  25       started_(false) {
  26 }
  27
  28 WebAudioCapturerSource::~WebAudioCapturerSource() {
  29 }
  30
  31 void WebAudioCapturerSource::setFormat(
  32     size_t number_of_channels, float sample_rate) {
  33   DVLOG(1) << "WebAudioCapturerSource::setFormat(sample_rate="
  34            << sample_rate << ")";
  35   if (number_of_channels <= 2) {
  36     set_format_channels_ = number_of_channels;
  37     ChannelLayout channel_layout =
  38         number_of_channels == 1 ? CHANNEL_LAYOUT_MONO : CHANNEL_LAYOUT_STEREO;
  39     capturer_->SetCapturerSource(this, channel_layout, sample_rate);
  40     capturer_->Start();
  41   } else {
  42     // TODO(crogers): Handle more than just the mono and stereo cases.
  43     LOG(WARNING) << "WebAudioCapturerSource::setFormat() : unhandled format.";
  44   }
  45 }
  46
  47 void WebAudioCapturerSource::Initialize(
  48     const media::AudioParameters& params,
  49     media::AudioCapturerSource::CaptureCallback* callback,
  50     int session_id) {
  51   // The downstream client should be configured the same as what WebKit
  52   // is feeding it.
  53   DCHECK_EQ(set_format_channels_, params.channels());
  54
  55   base::AutoLock auto_lock(lock_);
  56   params_ = params;
  57   callback_ = callback;
  58   wrapper_bus_ = AudioBus::CreateWrapper(params.channels());
  59   capture_bus_ = AudioBus::Create(params);
  60   fifo_.reset(new AudioFifo(params.channels(), kFifoSize));
  61 }
  62
  63 void WebAudioCapturerSource::Start() {
  64   started_ = true;
  65 }
  66
  67 void WebAudioCapturerSource::Stop() {
  68   started_ = false;
  69 }
  70
  71 void WebAudioCapturerSource::consumeAudio(
  72     const WebKit::WebVector<const float*>& audio_data,
  73     size_t number_of_frames) {
  74   base::AutoLock auto_lock(lock_);
  75
  76   if (!callback_)
  77     return;
  78
  79   wrapper_bus_->set_frames(number_of_frames);
  80
  81   // Make sure WebKit is honoring what it told us up front
  82   // about the channels.
  83   DCHECK_EQ(set_format_channels_, static_cast<int>(audio_data.size()));
  84   DCHECK_EQ(set_format_channels_, wrapper_bus_->channels());
  85
  86   for (size_t i = 0; i < audio_data.size(); ++i)
  87     wrapper_bus_->SetChannelData(i, const_cast<float*>(audio_data[i]));
  88
  89   // Handle mismatch between WebAudio buffer-size and WebRTC.
  90   int available = fifo_->max_frames() - fifo_->frames();
  91   if (available < static_cast<int>(number_of_frames)) {
  92     LOG(ERROR) << "WebAudioCapturerSource::Consume() : FIFO overrun.";
  93     return;
  94   }
  95
  96   fifo_->Push(wrapper_bus_.get());
  97   int capture_frames = params_.frames_per_buffer();
  98   while (fifo_->frames() >= capture_frames) {
  99     fifo_->Consume(capture_bus_.get(), 0, capture_frames);
 100     callback_->Capture(capture_bus_.get(), 0, 1.0);
 101   }
 102 }
 103
 104 }  // namespace content