diff options
Diffstat (limited to 'media/audio/audio_io.h')
-rw-r--r-- | media/audio/audio_io.h | 76 |
1 files changed, 0 insertions, 76 deletions
diff --git a/media/audio/audio_io.h b/media/audio/audio_io.h index 6e1e289..4f23686 100644 --- a/media/audio/audio_io.h +++ b/media/audio/audio_io.h @@ -153,80 +153,4 @@ class AudioInputStream { virtual ~AudioInputStream() {} }; -// Manages all audio resources. In particular it owns the AudioOutputStream -// objects. Provides some convenience functions that avoid the need to provide -// iterators over the existing streams. -class AudioManager { - public: - enum Format { - AUDIO_PCM_LINEAR = 0, // PCM is 'raw' amplitude samples. - AUDIO_PCM_LOW_LATENCY, // Linear PCM, low latency requested. - AUDIO_MOCK, // Creates a dummy AudioOutputStream object. - AUDIO_LAST_FORMAT // Only used for validation of format. - }; - - // Telephone quality sample rate, mostly for speech-only audio. - static const uint32 kTelephoneSampleRate = 8000; - // CD sampling rate is 44.1 KHz or conveniently 2x2x3x3x5x5x7x7. - static const uint32 kAudioCDSampleRate = 44100; - // Digital Audio Tape sample rate. - static const uint32 kAudioDATSampleRate = 48000; - - // Returns true if the OS reports existence of audio devices. This does not - // guarantee that the existing devices support all formats and sample rates. - virtual bool HasAudioOutputDevices() = 0; - - // Returns true if the OS reports existence of audio recording devices. This - // does not guarantee that the existing devices support all formats and - // sample rates. - virtual bool HasAudioInputDevices() = 0; - - // Factory for all the supported stream formats. The |channels| can be 1 to 5. - // The |sample_rate| is in hertz and can be any value supported by the - // platform. For some future formats the |sample_rate| and |bits_per_sample| - // can take special values. - // Returns NULL if the combination of the parameters is not supported, or if - // we have reached some other platform specific limit. - // - // AUDIO_PCM_LOW_LATENCY can be passed to this method and it has two effects: - // 1- Instead of triple buffered the audio will be double buffered. - // 2- A low latency driver or alternative audio subsystem will be used when - // available. - // - // Do not free the returned AudioOutputStream. It is owned by AudioManager. - virtual AudioOutputStream* MakeAudioOutputStream(Format format, int channels, - int sample_rate, - char bits_per_sample) = 0; - - // Factory to create audio recording streams. - // |channels| can be 1 or 2. - // |sample_rate| is in hertz and can be any value supported by the platform. - // |bits_per_sample| can be any value supported by the platform. - // |samples_per_packet| is in hertz as well and can be 0 to |sample_rate|, - // with 0 suggesting that the implementation use a default value for that - // platform. - // Returns NULL if the combination of the parameters is not supported, or if - // we have reached some other platform specific limit. - // - // Do not free the returned AudioInputStream. It is owned by AudioManager. - // When you are done with it, call |Stop()| and |Close()| to release it. - virtual AudioInputStream* MakeAudioInputStream(Format format, int channels, - int sample_rate, - char bits_per_sample, - uint32 samples_per_packet) = 0; - - // Muting continues playback but effectively the volume is set to zero. - // Un-muting returns the volume to the previous level. - virtual void MuteAll() = 0; - virtual void UnMuteAll() = 0; - - // Get AudioManager singleton. - // TODO(cpu): Define threading requirements for interacting with AudioManager. - static AudioManager* GetAudioManager(); - - protected: - virtual ~AudioManager() {} -}; - - #endif // MEDIA_AUDIO_AUDIO_IO_H_ |