media/audio/mac/audio_input_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_INPUT_MAC_H_
   6 #define MEDIA_AUDIO_MAC_AUDIO_INPUT_MAC_H_
   7
   8 #include <AudioToolbox/AudioFormat.h>
   9 #include <AudioToolbox/AudioQueue.h>
  10
  11 #include "base/cancelable_callback.h"
  12 #include "base/compiler_specific.h"
  13 #include "base/time/time.h"
  14 #include "media/audio/audio_io.h"
  15 #include "media/audio/audio_parameters.h"
  16
  17 namespace media {
  18
  19 class AudioBus;
  20 class AudioManagerMac;
  21
  22 // Implementation of AudioInputStream for Mac OS X using the audio queue service
  23 // present in OS 10.5 and later. Design reflects PCMQueueOutAudioOutputStream.
  24 class PCMQueueInAudioInputStream : public AudioInputStream {
  25  public:
  26   // Parameters as per AudioManager::MakeAudioInputStream.
  27   PCMQueueInAudioInputStream(AudioManagerMac* manager,
  28                              const AudioParameters& params);
  29   ~PCMQueueInAudioInputStream() override;
  30
  31   // Implementation of AudioInputStream.
  32   bool Open() override;
  33   void Start(AudioInputCallback* callback) override;
  34   void Stop() override;
  35   void Close() override;
  36   double GetMaxVolume() override;
  37   void SetVolume(double volume) override;
  38   double GetVolume() override;
  39   bool SetAutomaticGainControl(bool enabled) override;
  40   bool GetAutomaticGainControl() override;
  41   bool IsMuted() override;
  42
  43  private:
  44   // Issue the OnError to |callback_|;
  45   void HandleError(OSStatus err);
  46
  47   // Allocates and prepares the memory that will be used for recording.
  48   bool SetupBuffers();
  49
  50   // Sends a buffer to the audio driver for recording.
  51   OSStatus QueueNextBuffer(AudioQueueBufferRef audio_buffer);
  52
  53   // Callback from OS, delegates to non-static version below.
  54   static void HandleInputBufferStatic(
  55       void* data,
  56       AudioQueueRef audio_queue,
  57       AudioQueueBufferRef audio_buffer,
  58       const AudioTimeStamp* start_time,
  59       UInt32 num_packets,
  60       const AudioStreamPacketDescription* desc);
  61
  62   // Handles callback from OS. Will be called on OS internal thread.
  63   void HandleInputBuffer(AudioQueueRef audio_queue,
  64                          AudioQueueBufferRef audio_buffer,
  65                          const AudioTimeStamp* start_time,
  66                          UInt32 num_packets,
  67                          const AudioStreamPacketDescription* packet_desc);
  68
  69   static const int kNumberBuffers = 3;
  70
  71   // Manager that owns this stream, used for closing down.
  72   AudioManagerMac* manager_;
  73   // We use the callback mostly to periodically supply the recorded audio data.
  74   AudioInputCallback* callback_;
  75   // Structure that holds the stream format details such as bitrate.
  76   AudioStreamBasicDescription format_;
  77   // Handle to the OS audio queue object.
  78   AudioQueueRef audio_queue_;
  79   // Size of each of the buffers in |audio_buffers_|
  80   uint32 buffer_size_bytes_;
  81   // True iff Start() has been called successfully.
  82   bool started_;
  83   // Used to determine if we need to slow down |callback_| calls.
  84   base::TimeTicks last_fill_;
  85   // Used to defer Start() to workaround http://crbug.com/160920.
  86   base::CancelableClosure deferred_start_cb_;
  87
  88   scoped_ptr<media::AudioBus> audio_bus_;
  89
  90   DISALLOW_COPY_AND_ASSIGN(PCMQueueInAudioInputStream);
  91 };
  92
  93 }  // namespace media
  94
  95 #endif  // MEDIA_AUDIO_MAC_AUDIO_INPUT_MAC_H_