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 #ifndef MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_ 6 #define MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_ 7 8 #include <string> 9 #include <utility> 10 11 #include "base/compiler_specific.h" 12 #include "base/memory/scoped_ptr.h" 13 #include "base/memory/scoped_vector.h" 14 #include "base/observer_list.h" 15 #include "base/threading/thread.h" 16 #include "media/audio/audio_manager.h" 17 18 #include "media/audio/audio_output_dispatcher.h" 19 20 #if defined(OS_WIN) 21 #include "base/win/scoped_com_initializer.h" 22 #endif 23 24 namespace media { 25 26 class AudioOutputDispatcher; 27 28 // AudioManagerBase provides AudioManager functions common for all platforms. 29 class MEDIA_EXPORT AudioManagerBase : public AudioManager { 30 public: 31 // TODO(sergeyu): The constants below belong to AudioManager interface, not 32 // to the base implementation. 33 34 // Name of the generic "default" device. 35 static const char kDefaultDeviceName[]; 36 // Unique Id of the generic "default" device. 37 static const char kDefaultDeviceId[]; 38 39 // Input device ID used to capture the default system playback stream. When 40 // this device ID is passed to MakeAudioInputStream() the returned 41 // AudioInputStream will be capturing audio currently being played on the 42 // default playback device. At the moment this feature is supported only on 43 // some platforms. AudioInputStream::Intialize() will return an error on 44 // platforms that don't support it. GetInputStreamParameters() must be used 45 // to get the parameters of the loopback device before creating a loopback 46 // stream, otherwise stream initialization may fail. 47 static const char kLoopbackInputDeviceId[]; 48 49 virtual ~AudioManagerBase(); 50 51 virtual scoped_refptr<base::MessageLoopProxy> GetMessageLoop() OVERRIDE; 52 virtual scoped_refptr<base::MessageLoopProxy> GetWorkerLoop() OVERRIDE; 53 54 virtual base::string16 GetAudioInputDeviceModel() OVERRIDE; 55 56 virtual void ShowAudioInputSettings() OVERRIDE; 57 58 virtual void GetAudioInputDeviceNames( 59 AudioDeviceNames* device_names) OVERRIDE; 60 61 virtual void GetAudioOutputDeviceNames( 62 AudioDeviceNames* device_names) OVERRIDE; 63 64 virtual AudioOutputStream* MakeAudioOutputStream( 65 const AudioParameters& params, 66 const std::string& device_id, 67 const std::string& input_device_id) OVERRIDE; 68 69 virtual AudioInputStream* MakeAudioInputStream( 70 const AudioParameters& params, const std::string& device_id) OVERRIDE; 71 72 virtual AudioOutputStream* MakeAudioOutputStreamProxy( 73 const AudioParameters& params, 74 const std::string& device_id, 75 const std::string& input_device_id) OVERRIDE; 76 77 // Called internally by the audio stream when it has been closed. 78 virtual void ReleaseOutputStream(AudioOutputStream* stream); 79 virtual void ReleaseInputStream(AudioInputStream* stream); 80 81 // Creates the output stream for the |AUDIO_PCM_LINEAR| format. The legacy 82 // name is also from |AUDIO_PCM_LINEAR|. 83 virtual AudioOutputStream* MakeLinearOutputStream( 84 const AudioParameters& params) = 0; 85 86 // Creates the output stream for the |AUDIO_PCM_LOW_LATENCY| format. 87 // |input_device_id| is used by unified IO to open the correct input device. 88 virtual AudioOutputStream* MakeLowLatencyOutputStream( 89 const AudioParameters& params, 90 const std::string& device_id, 91 const std::string& input_device_id) = 0; 92 93 // Creates the input stream for the |AUDIO_PCM_LINEAR| format. The legacy 94 // name is also from |AUDIO_PCM_LINEAR|. 95 virtual AudioInputStream* MakeLinearInputStream( 96 const AudioParameters& params, const std::string& device_id) = 0; 97 98 // Creates the input stream for the |AUDIO_PCM_LOW_LATENCY| format. 99 virtual AudioInputStream* MakeLowLatencyInputStream( 100 const AudioParameters& params, const std::string& device_id) = 0; 101 102 // Listeners will be notified on the AudioManager::GetMessageLoop() loop. 103 virtual void AddOutputDeviceChangeListener( 104 AudioDeviceListener* listener) OVERRIDE; 105 virtual void RemoveOutputDeviceChangeListener( 106 AudioDeviceListener* listener) OVERRIDE; 107 108 virtual AudioParameters GetDefaultOutputStreamParameters() OVERRIDE; 109 virtual AudioParameters GetOutputStreamParameters( 110 const std::string& device_id) OVERRIDE; 111 112 virtual AudioParameters GetInputStreamParameters( 113 const std::string& device_id) OVERRIDE; 114 115 virtual std::string GetAssociatedOutputDeviceID( 116 const std::string& input_device_id) OVERRIDE; 117 118 virtual scoped_ptr<AudioLog> CreateAudioLog( 119 AudioLogFactory::AudioComponent component) OVERRIDE; 120 121 virtual void FixWedgedAudio() OVERRIDE; 122 123 protected: 124 AudioManagerBase(AudioLogFactory* audio_log_factory); 125 126 // Shuts down the audio thread and releases all the audio output dispatchers 127 // on the audio thread. All audio streams should be freed before Shutdown() 128 // is called. This must be called in the destructor of every AudioManagerBase 129 // implementation. 130 void Shutdown(); 131 132 void SetMaxOutputStreamsAllowed(int max) { max_num_output_streams_ = max; } 133 134 // Called by each platform specific AudioManager to notify output state change 135 // listeners that a state change has occurred. Must be called from the audio 136 // thread. 137 void NotifyAllOutputDeviceChangeListeners(); 138 139 // Returns user buffer size as specified on the command line or 0 if no buffer 140 // size has been specified. 141 int GetUserBufferSize(); 142 143 // Returns the preferred hardware audio output parameters for opening output 144 // streams. If the users inject a valid |input_params|, each AudioManager 145 // will decide if they should return the values from |input_params| or the 146 // default hardware values. If the |input_params| is invalid, it will return 147 // the default hardware audio parameters. 148 // If |output_device_id| is empty, the implementation must treat that as 149 // a request for the default output device. 150 virtual AudioParameters GetPreferredOutputStreamParameters( 151 const std::string& output_device_id, 152 const AudioParameters& input_params) = 0; 153 154 // Returns the ID of the default audio output device. 155 // Implementations that don't yet support this should return an empty string. 156 virtual std::string GetDefaultOutputDeviceID(); 157 158 // Get number of input or output streams. 159 int input_stream_count() { return num_input_streams_; } 160 int output_stream_count() { return num_output_streams_; } 161 162 private: 163 struct DispatcherParams; 164 typedef ScopedVector<DispatcherParams> AudioOutputDispatchers; 165 166 class CompareByParams; 167 168 // Called by Shutdown(). 169 void ShutdownOnAudioThread(); 170 171 // Max number of open output streams, modified by 172 // SetMaxOutputStreamsAllowed(). 173 int max_num_output_streams_; 174 175 // Max number of open input streams. 176 int max_num_input_streams_; 177 178 // Number of currently open output streams. 179 int num_output_streams_; 180 181 // Number of currently open input streams. 182 int num_input_streams_; 183 184 // Track output state change listeners. 185 ObserverList<AudioDeviceListener> output_listeners_; 186 187 // Thread used to interact with audio streams created by this audio manager. 188 base::Thread audio_thread_; 189 190 // The message loop of the audio thread this object runs on. Used for internal 191 // tasks which run on the audio thread even after Shutdown() has been started 192 // and GetMessageLoop() starts returning NULL. 193 scoped_refptr<base::MessageLoopProxy> message_loop_; 194 195 // Map of cached AudioOutputDispatcher instances. Must only be touched 196 // from the audio thread (no locking). 197 AudioOutputDispatchers output_dispatchers_; 198 199 // Proxy for creating AudioLog objects. 200 AudioLogFactory* const audio_log_factory_; 201 202 DISALLOW_COPY_AND_ASSIGN(AudioManagerBase); 203 }; 204 205 } // namespace media 206 207 #endif // MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_ 208
