media/audio/mac/audio_manager_mac.h

   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_MAC_AUDIO_MANAGER_MAC_H_
   6 #define MEDIA_AUDIO_MAC_AUDIO_MANAGER_MAC_H_
   7
   8 #include <AudioUnit/AudioUnit.h>
   9 #include <CoreAudio/AudioHardware.h>
  10 #include <list>
  11 #include <string>
  12
  13 #include "base/basictypes.h"
  14 #include "base/compiler_specific.h"
  15 #include "media/audio/audio_manager_base.h"
  16 #include "media/audio/mac/audio_device_listener_mac.h"
  17
  18 namespace media {
  19
  20 class AUAudioInputStream;
  21 class AUHALStream;
  22
  23 // Mac OS X implementation of the AudioManager singleton. This class is internal
  24 // to the audio output and only internal users can call methods not exposed by
  25 // the AudioManager class.
  26 class MEDIA_EXPORT AudioManagerMac : public AudioManagerBase {
  27  public:
  28   AudioManagerMac(AudioLogFactory* audio_log_factory);
  29
  30   // Implementation of AudioManager.
  31   bool HasAudioOutputDevices() override;
  32   bool HasAudioInputDevices() override;
  33   void GetAudioInputDeviceNames(AudioDeviceNames* device_names) override;
  34   void GetAudioOutputDeviceNames(AudioDeviceNames* device_names) override;
  35   AudioParameters GetInputStreamParameters(
  36       const std::string& device_id) override;
  37   std::string GetAssociatedOutputDeviceID(
  38       const std::string& input_device_id) override;
  39
  40   // Implementation of AudioManagerBase.
  41   AudioOutputStream* MakeLinearOutputStream(
  42       const AudioParameters& params) override;
  43   AudioOutputStream* MakeLowLatencyOutputStream(
  44       const AudioParameters& params,
  45       const std::string& device_id) override;
  46   AudioInputStream* MakeLinearInputStream(
  47       const AudioParameters& params,
  48       const std::string& device_id) override;
  49   AudioInputStream* MakeLowLatencyInputStream(
  50       const AudioParameters& params,
  51       const std::string& device_id) override;
  52   std::string GetDefaultOutputDeviceID() override;
  53
  54   // Used to track destruction of input and output streams.
  55   void ReleaseOutputStream(AudioOutputStream* stream) override;
  56   void ReleaseInputStream(AudioInputStream* stream) override;
  57
  58   static bool GetDefaultInputDevice(AudioDeviceID* device);
  59   static bool GetDefaultOutputDevice(AudioDeviceID* device);
  60   static bool GetDefaultDevice(AudioDeviceID* device, bool input);
  61
  62   static bool GetDefaultOutputChannels(int* channels);
  63
  64   static bool GetDeviceChannels(AudioDeviceID device,
  65                                 AudioObjectPropertyScope scope,
  66                                 int* channels);
  67
  68   static int HardwareSampleRateForDevice(AudioDeviceID device_id);
  69   static int HardwareSampleRate();
  70
  71   // OSX has issues with starting streams as the sytem goes into suspend and
  72   // immediately after it wakes up from resume.  See http://crbug.com/160920.
  73   // As a workaround we delay Start() when it occurs after suspend and for a
  74   // small amount of time after resume.
  75   //
  76   // Streams should consult ShouldDeferStreamStart() and if true check the value
  77   // again after |kStartDelayInSecsForPowerEvents| has elapsed. If false, the
  78   // stream may be started immediately.
  79   enum { kStartDelayInSecsForPowerEvents = 1 };
  80   bool ShouldDeferStreamStart();
  81
  82   // Changes the buffer size for |device_id| if there are no active input or
  83   // output streams on the device or |desired_buffer_size| is lower than the
  84   // current device buffer size.
  85   //
  86   // Returns false if an error occurred. There is no indication if the buffer
  87   // size was changed or not.
  88   // |element| is 0 for output streams and 1 for input streams.
  89   // TODO(dalecurtis): we could change the the last parameter to an input/output
  90   // pointer so it can be updated if the buffer size is not changed.
  91   // See http://crbug.com/428706 for details.
  92   bool MaybeChangeBufferSize(AudioDeviceID device_id,
  93                              AudioUnit audio_unit,
  94                              AudioUnitElement element,
  95                              size_t desired_buffer_size);
  96
  97  protected:
  98   ~AudioManagerMac() override;
  99
 100   AudioParameters GetPreferredOutputStreamParameters(
 101       const std::string& output_device_id,
 102       const AudioParameters& input_params) override;
 103
 104  private:
 105   void InitializeOnAudioThread();
 106   void ShutdownOnAudioThread();
 107
 108   int ChooseBufferSize(bool is_input, int sample_rate);
 109
 110   // Notify streams of a device change if the default output device or its
 111   // sample rate has changed, otherwise does nothing.
 112   void HandleDeviceChanges();
 113
 114   scoped_ptr<AudioDeviceListenerMac> output_device_listener_;
 115
 116   // Track the output sample-rate and the default output device
 117   // so we can intelligently handle device notifications only when necessary.
 118   int current_sample_rate_;
 119   AudioDeviceID current_output_device_;
 120
 121   // Helper class which monitors power events to determine if output streams
 122   // should defer Start() calls.  Required to workaround an OSX bug.  See
 123   // http://crbug.com/160920 for more details.
 124   class AudioPowerObserver;
 125   scoped_ptr<AudioPowerObserver> power_observer_;
 126
 127   // Tracks all constructed input and output streams so they can be stopped at
 128   // shutdown.  See ShutdownOnAudioThread() for more details.
 129   std::list<AudioInputStream*> basic_input_streams_;
 130   std::list<AUAudioInputStream*> low_latency_input_streams_;
 131   std::list<AUHALStream*> output_streams_;
 132
 133   DISALLOW_COPY_AND_ASSIGN(AudioManagerMac);
 134 };
 135
 136 }  // namespace media
 137
 138 #endif  // MEDIA_AUDIO_MAC_AUDIO_MANAGER_MAC_H_