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/audio_renderer_mixer_manager.h"
6
7 #include "base/bind.h"
8 #include "base/bind_helpers.h"
9 #include "content/renderer/media/audio_device_factory.h"
10 #include "media/audio/audio_output_device.h"
11 #include "media/base/audio_hardware_config.h"
12 #include "media/base/audio_renderer_mixer.h"
13 #include "media/base/audio_renderer_mixer_input.h"
14
15 namespace content {
16
AudioRendererMixerManager(media::AudioHardwareConfig * hardware_config)17 AudioRendererMixerManager::AudioRendererMixerManager(
18 media::AudioHardwareConfig* hardware_config)
19 : hardware_config_(hardware_config),
20 sink_for_testing_(NULL) {
21 }
22
~AudioRendererMixerManager()23 AudioRendererMixerManager::~AudioRendererMixerManager() {
24 DCHECK(mixers_.empty());
25 }
26
CreateInput(int source_render_view_id,int source_render_frame_id)27 media::AudioRendererMixerInput* AudioRendererMixerManager::CreateInput(
28 int source_render_view_id, int source_render_frame_id) {
29 return new media::AudioRendererMixerInput(
30 base::Bind(
31 &AudioRendererMixerManager::GetMixer, base::Unretained(this),
32 source_render_view_id,
33 source_render_frame_id),
34 base::Bind(
35 &AudioRendererMixerManager::RemoveMixer, base::Unretained(this),
36 source_render_view_id));
37 }
38
SetAudioRendererSinkForTesting(media::AudioRendererSink * sink)39 void AudioRendererMixerManager::SetAudioRendererSinkForTesting(
40 media::AudioRendererSink* sink) {
41 sink_for_testing_ = sink;
42 }
43
GetMixer(int source_render_view_id,int source_render_frame_id,const media::AudioParameters & params)44 media::AudioRendererMixer* AudioRendererMixerManager::GetMixer(
45 int source_render_view_id,
46 int source_render_frame_id,
47 const media::AudioParameters& params) {
48 const MixerKey key(source_render_view_id, params);
49 base::AutoLock auto_lock(mixers_lock_);
50
51 AudioRendererMixerMap::iterator it = mixers_.find(key);
52 if (it != mixers_.end()) {
53 it->second.ref_count++;
54 return it->second.mixer;
55 }
56
57 // On ChromeOS and Linux we can rely on the playback device to handle
58 // resampling, so don't waste cycles on it here.
59 #if defined(OS_CHROMEOS) || defined(OS_LINUX)
60 int sample_rate = params.sample_rate();
61 #else
62 int sample_rate = hardware_config_->GetOutputSampleRate();
63 #endif
64
65 // Create output parameters based on the audio hardware configuration for
66 // passing on to the output sink. Force to 16-bit output for now since we
67 // know that works well for WebAudio and WebRTC.
68 media::AudioParameters output_params(
69 media::AudioParameters::AUDIO_PCM_LOW_LATENCY, params.channel_layout(),
70 sample_rate, 16, hardware_config_->GetHighLatencyBufferSize());
71
72 // If we've created invalid output parameters, simply pass on the input params
73 // and let the browser side handle automatic fallback.
74 if (!output_params.IsValid())
75 output_params = params;
76
77 media::AudioRendererMixer* mixer;
78 if (sink_for_testing_) {
79 mixer = new media::AudioRendererMixer(
80 params, output_params, sink_for_testing_);
81 } else {
82 mixer = new media::AudioRendererMixer(
83 params, output_params, AudioDeviceFactory::NewOutputDevice(
84 source_render_view_id, source_render_frame_id));
85 }
86
87 AudioRendererMixerReference mixer_reference = { mixer, 1 };
88 mixers_[key] = mixer_reference;
89 return mixer;
90 }
91
RemoveMixer(int source_render_view_id,const media::AudioParameters & params)92 void AudioRendererMixerManager::RemoveMixer(
93 int source_render_view_id,
94 const media::AudioParameters& params) {
95 const MixerKey key(source_render_view_id, params);
96 base::AutoLock auto_lock(mixers_lock_);
97
98 AudioRendererMixerMap::iterator it = mixers_.find(key);
99 DCHECK(it != mixers_.end());
100
101 // Only remove the mixer if AudioRendererMixerManager is the last owner.
102 it->second.ref_count--;
103 if (it->second.ref_count == 0) {
104 delete it->second.mixer;
105 mixers_.erase(it);
106 }
107 }
108
109 } // namespace content
110