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 "media/base/audio_renderer_mixer_input.h"
6
7 #include "base/bind.h"
8 #include "base/logging.h"
9 #include "media/base/audio_renderer_mixer.h"
10
11 namespace media {
12
AudioRendererMixerInput(const GetMixerCB & get_mixer_cb,const RemoveMixerCB & remove_mixer_cb)13 AudioRendererMixerInput::AudioRendererMixerInput(
14 const GetMixerCB& get_mixer_cb, const RemoveMixerCB& remove_mixer_cb)
15 : playing_(false),
16 initialized_(false),
17 volume_(1.0f),
18 get_mixer_cb_(get_mixer_cb),
19 remove_mixer_cb_(remove_mixer_cb),
20 mixer_(NULL),
21 callback_(NULL),
22 error_cb_(base::Bind(
23 &AudioRendererMixerInput::OnRenderError, base::Unretained(this))) {
24 }
25
~AudioRendererMixerInput()26 AudioRendererMixerInput::~AudioRendererMixerInput() {
27 DCHECK(!playing_);
28 DCHECK(!mixer_);
29 }
30
Initialize(const AudioParameters & params,AudioRendererSink::RenderCallback * callback)31 void AudioRendererMixerInput::Initialize(
32 const AudioParameters& params,
33 AudioRendererSink::RenderCallback* callback) {
34 DCHECK(callback);
35 DCHECK(!initialized_);
36
37 params_ = params;
38 callback_ = callback;
39 initialized_ = true;
40 }
41
Start()42 void AudioRendererMixerInput::Start() {
43 DCHECK(initialized_);
44 DCHECK(!playing_);
45 DCHECK(!mixer_);
46 mixer_ = get_mixer_cb_.Run(params_);
47
48 // Note: OnRenderError() may be called immediately after this call returns.
49 mixer_->AddErrorCallback(error_cb_);
50 }
51
Stop()52 void AudioRendererMixerInput::Stop() {
53 // Stop() may be called at any time, if Pause() hasn't been called we need to
54 // remove our mixer input before shutdown.
55 if (playing_) {
56 mixer_->RemoveMixerInput(this);
57 playing_ = false;
58 }
59
60 if (mixer_) {
61 // TODO(dalecurtis): This is required so that |callback_| isn't called after
62 // Stop() by an error event since it may outlive this ref-counted object. We
63 // should instead have sane ownership semantics: http://crbug.com/151051
64 mixer_->RemoveErrorCallback(error_cb_);
65 remove_mixer_cb_.Run(params_);
66 mixer_ = NULL;
67 }
68 }
69
Play()70 void AudioRendererMixerInput::Play() {
71 DCHECK(initialized_);
72 DCHECK(mixer_);
73
74 if (playing_)
75 return;
76
77 mixer_->AddMixerInput(this);
78 playing_ = true;
79 }
80
Pause()81 void AudioRendererMixerInput::Pause() {
82 DCHECK(initialized_);
83 DCHECK(mixer_);
84
85 if (!playing_)
86 return;
87
88 mixer_->RemoveMixerInput(this);
89 playing_ = false;
90 }
91
SetVolume(double volume)92 bool AudioRendererMixerInput::SetVolume(double volume) {
93 volume_ = volume;
94 return true;
95 }
96
ProvideInput(AudioBus * audio_bus,base::TimeDelta buffer_delay)97 double AudioRendererMixerInput::ProvideInput(AudioBus* audio_bus,
98 base::TimeDelta buffer_delay) {
99 int frames_filled = callback_->Render(
100 audio_bus, static_cast<int>(buffer_delay.InMillisecondsF() + 0.5));
101
102 // AudioConverter expects unfilled frames to be zeroed.
103 if (frames_filled < audio_bus->frames()) {
104 audio_bus->ZeroFramesPartial(
105 frames_filled, audio_bus->frames() - frames_filled);
106 }
107
108 return frames_filled > 0 ? volume_ : 0;
109 }
110
OnRenderError()111 void AudioRendererMixerInput::OnRenderError() {
112 callback_->OnRenderError();
113 }
114
115 } // namespace media
116