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 // References to AudioRendererMixers may be owned by garbage collected
25 // objects. During process shutdown they may be leaked, so, transitively,
26 // |mixers_| may leak (i.e., may be non-empty at this time) as well.
27 }
28
CreateInput(int source_render_view_id,int source_render_frame_id)29 media::AudioRendererMixerInput* AudioRendererMixerManager::CreateInput(
30 int source_render_view_id, int source_render_frame_id) {
31 return new media::AudioRendererMixerInput(
32 base::Bind(
33 &AudioRendererMixerManager::GetMixer, base::Unretained(this),
34 source_render_view_id,
35 source_render_frame_id),
36 base::Bind(
37 &AudioRendererMixerManager::RemoveMixer, base::Unretained(this),
38 source_render_view_id));
39 }
40
SetAudioRendererSinkForTesting(media::AudioRendererSink * sink)41 void AudioRendererMixerManager::SetAudioRendererSinkForTesting(
42 media::AudioRendererSink* sink) {
43 sink_for_testing_ = sink;
44 }
45
GetMixer(int source_render_view_id,int source_render_frame_id,const media::AudioParameters & params)46 media::AudioRendererMixer* AudioRendererMixerManager::GetMixer(
47 int source_render_view_id,
48 int source_render_frame_id,
49 const media::AudioParameters& params) {
50 // Effects are not passed through to output creation, so ensure none are set.
51 DCHECK_EQ(params.effects(), media::AudioParameters::NO_EFFECTS);
52
53 const MixerKey key(source_render_view_id, params);
54 base::AutoLock auto_lock(mixers_lock_);
55
56 AudioRendererMixerMap::iterator it = mixers_.find(key);
57 if (it != mixers_.end()) {
58 it->second.ref_count++;
59 return it->second.mixer;
60 }
61
62 // On ChromeOS we can rely on the playback device to handle resampling, so
63 // don't waste cycles on it here.
64 #if defined(OS_CHROMEOS)
65 int sample_rate = params.sample_rate();
66 #else
67 int sample_rate = hardware_config_->GetOutputSampleRate();
68 #endif
69
70 // Create output parameters based on the audio hardware configuration for
71 // passing on to the output sink. Force to 16-bit output for now since we
72 // know that works everywhere; ChromeOS does not support other bit depths.
73 media::AudioParameters output_params(
74 media::AudioParameters::AUDIO_PCM_LOW_LATENCY, params.channel_layout(),
75 sample_rate, 16, hardware_config_->GetHighLatencyBufferSize());
76
77 // If we've created invalid output parameters, simply pass on the input params
78 // and let the browser side handle automatic fallback.
79 if (!output_params.IsValid())
80 output_params = params;
81
82 media::AudioRendererMixer* mixer;
83 if (sink_for_testing_) {
84 mixer = new media::AudioRendererMixer(
85 params, output_params, sink_for_testing_);
86 } else {
87 mixer = new media::AudioRendererMixer(
88 params, output_params, AudioDeviceFactory::NewOutputDevice(
89 source_render_view_id, source_render_frame_id));
90 }
91
92 AudioRendererMixerReference mixer_reference = { mixer, 1 };
93 mixers_[key] = mixer_reference;
94 return mixer;
95 }
96
RemoveMixer(int source_render_view_id,const media::AudioParameters & params)97 void AudioRendererMixerManager::RemoveMixer(
98 int source_render_view_id,
99 const media::AudioParameters& params) {
100 const MixerKey key(source_render_view_id, params);
101 base::AutoLock auto_lock(mixers_lock_);
102
103 AudioRendererMixerMap::iterator it = mixers_.find(key);
104 DCHECK(it != mixers_.end());
105
106 // Only remove the mixer if AudioRendererMixerManager is the last owner.
107 it->second.ref_count--;
108 if (it->second.ref_count == 0) {
109 delete it->second.mixer;
110 mixers_.erase(it);
111 }
112 }
113
114 } // namespace content
115