audio_manager_mac.h revision e4256316f8b5e8d1ec0df1f7762771622a53fa63 
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 <CoreAudio/AudioHardware.h>
9#include <list>
10#include <string>
11
12#include "base/basictypes.h"
13#include "base/compiler_specific.h"
14#include "media/audio/audio_manager_base.h"
15#include "media/audio/mac/audio_device_listener_mac.h"
16
17namespace media {
18
19// Mac OS X implementation of the AudioManager singleton. This class is internal
20// to the audio output and only internal users can call methods not exposed by
21// the AudioManager class.
22class MEDIA_EXPORT AudioManagerMac : public AudioManagerBase {
23 public:
24  AudioManagerMac(AudioLogFactory* audio_log_factory);
25
26  // Implementation of AudioManager.
27  virtual bool HasAudioOutputDevices() OVERRIDE;
28  virtual bool HasAudioInputDevices() OVERRIDE;
29  virtual void GetAudioInputDeviceNames(
30      AudioDeviceNames* device_names) OVERRIDE;
31  virtual void GetAudioOutputDeviceNames(
32      AudioDeviceNames* device_names) OVERRIDE;
33  virtual AudioParameters GetInputStreamParameters(
34      const std::string& device_id) OVERRIDE;
35  virtual std::string GetAssociatedOutputDeviceID(
36      const std::string& input_device_id) OVERRIDE;
37
38  // Implementation of AudioManagerBase.
39  virtual AudioOutputStream* MakeLinearOutputStream(
40      const AudioParameters& params) OVERRIDE;
41  virtual AudioOutputStream* MakeLowLatencyOutputStream(
42      const AudioParameters& params,
43      const std::string& device_id) OVERRIDE;
44  virtual AudioInputStream* MakeLinearInputStream(
45      const AudioParameters& params, const std::string& device_id) OVERRIDE;
46  virtual AudioInputStream* MakeLowLatencyInputStream(
47      const AudioParameters& params, const std::string& device_id) OVERRIDE;
48  virtual std::string GetDefaultOutputDeviceID() OVERRIDE;
49
50  // Used to track destruction of input and output streams.
51  virtual void ReleaseOutputStream(AudioOutputStream* stream) OVERRIDE;
52  virtual void ReleaseInputStream(AudioInputStream* stream) OVERRIDE;
53
54  static bool GetDefaultInputDevice(AudioDeviceID* device);
55  static bool GetDefaultOutputDevice(AudioDeviceID* device);
56  static bool GetDefaultDevice(AudioDeviceID* device, bool input);
57
58  static bool GetDefaultOutputChannels(int* channels);
59
60  static bool GetDeviceChannels(AudioDeviceID device,
61                                AudioObjectPropertyScope scope,
62                                int* channels);
63
64  static int HardwareSampleRateForDevice(AudioDeviceID device_id);
65  static int HardwareSampleRate();
66
67  // OSX has issues with starting streams as the sytem goes into suspend and
68  // immediately after it wakes up from resume.  See http://crbug.com/160920.
69  // As a workaround we delay Start() when it occurs after suspend and for a
70  // small amount of time after resume.
71  //
72  // Streams should consult ShouldDeferStreamStart() and if true check the value
73  // again after |kStartDelayInSecsForPowerEvents| has elapsed. If false, the
74  // stream may be started immediately.
75  enum { kStartDelayInSecsForPowerEvents = 1 };
76  bool ShouldDeferStreamStart();
77
78 protected:
79  virtual ~AudioManagerMac();
80
81  virtual AudioParameters GetPreferredOutputStreamParameters(
82      const std::string& output_device_id,
83      const AudioParameters& input_params) OVERRIDE;
84
85 private:
86  void InitializeOnAudioThread();
87  void ShutdownOnAudioThread();
88
89  int ChooseBufferSize(bool is_input, int sample_rate);
90
91  // Notify streams of a device change if the default output device or its
92  // sample rate has changed, otherwise does nothing.
93  void HandleDeviceChanges();
94
95  scoped_ptr<AudioDeviceListenerMac> output_device_listener_;
96
97  // Track the output sample-rate and the default output device
98  // so we can intelligently handle device notifications only when necessary.
99  int current_sample_rate_;
100  AudioDeviceID current_output_device_;
101
102  // Helper class which monitors power events to determine if output streams
103  // should defer Start() calls.  Required to workaround an OSX bug.  See
104  // http://crbug.com/160920 for more details.
105  class AudioPowerObserver;
106  scoped_ptr<AudioPowerObserver> power_observer_;
107
108  // Tracks all constructed input and output streams so they can be stopped at
109  // shutdown.  See ShutdownOnAudioThread() for more details.
110  std::list<AudioInputStream*> input_streams_;
111  std::list<AudioOutputStream*> output_streams_;
112
113  DISALLOW_COPY_AND_ASSIGN(AudioManagerMac);
114};
115
116}  // namespace media
117
118#endif  // MEDIA_AUDIO_MAC_AUDIO_MANAGER_MAC_H_
119