media/audio/android/opensles_input.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_ANDROID_OPENSLES_INPUT_H_
   6 #define MEDIA_AUDIO_ANDROID_OPENSLES_INPUT_H_
   7
   8 #include <SLES/OpenSLES.h>
   9 #include <SLES/OpenSLES_Android.h>
  10
  11 #include "base/compiler_specific.h"
  12 #include "base/synchronization/lock.h"
  13 #include "base/threading/thread_checker.h"
  14 #include "media/audio/android/opensles_util.h"
  15 #include "media/audio/audio_io.h"
  16 #include "media/audio/audio_parameters.h"
  17
  18 namespace media {
  19
  20 class AudioManagerAndroid;
  21
  22 // Implements PCM audio input support for Android using the OpenSLES API.
  23 // This class is created and lives on the Audio Manager thread but recorded
  24 // audio buffers are delivered on an internal OpenSLES audio thread. All public
  25 // methods should be called on the Audio Manager thread.
  26 class OpenSLESInputStream : public AudioInputStream {
  27  public:
  28   static const int kMaxNumOfBuffersInQueue = 2;
  29
  30   OpenSLESInputStream(AudioManagerAndroid* manager,
  31                       const AudioParameters& params);
  32
  33   virtual ~OpenSLESInputStream();
  34
  35   // Implementation of AudioInputStream.
  36   virtual bool Open() OVERRIDE;
  37   virtual void Start(AudioInputCallback* callback) OVERRIDE;
  38   virtual void Stop() OVERRIDE;
  39   virtual void Close() OVERRIDE;
  40   virtual double GetMaxVolume() OVERRIDE;
  41   virtual void SetVolume(double volume) OVERRIDE;
  42   virtual double GetVolume() OVERRIDE;
  43   virtual void SetAutomaticGainControl(bool enabled) OVERRIDE;
  44   virtual bool GetAutomaticGainControl() OVERRIDE;
  45
  46  private:
  47   bool CreateRecorder();
  48
  49   // Called from OpenSLES specific audio worker thread.
  50   static void SimpleBufferQueueCallback(
  51       SLAndroidSimpleBufferQueueItf buffer_queue,
  52       void* instance);
  53
  54   // Called from OpenSLES specific audio worker thread.
  55   void ReadBufferQueue();
  56
  57   // Called in Open();
  58   void SetupAudioBuffer();
  59
  60   // Called in Close();
  61   void ReleaseAudioBuffer();
  62
  63   // If OpenSLES reports an error this function handles it and passes it to
  64   // the attached AudioInputCallback::OnError().
  65   void HandleError(SLresult error);
  66
  67   base::ThreadChecker thread_checker_;
  68
  69   // Protects |callback_|, |active_buffer_index_|, |audio_data_|,
  70   // |buffer_size_bytes_| and |simple_buffer_queue_|.
  71   base::Lock lock_;
  72
  73   AudioManagerAndroid* audio_manager_;
  74
  75   AudioInputCallback* callback_;
  76
  77   // Shared engine interfaces for the app.
  78   media::ScopedSLObjectItf recorder_object_;
  79   media::ScopedSLObjectItf engine_object_;
  80
  81   SLRecordItf recorder_;
  82
  83   // Buffer queue recorder interface.
  84   SLAndroidSimpleBufferQueueItf simple_buffer_queue_;
  85
  86   SLDataFormat_PCM format_;
  87
  88   // Audio buffers that are allocated in the constructor based on
  89   // info from audio parameters.
  90   uint8* audio_data_[kMaxNumOfBuffersInQueue];
  91
  92   int active_buffer_index_;
  93   int buffer_size_bytes_;
  94
  95   bool started_;
  96
  97   DISALLOW_COPY_AND_ASSIGN(OpenSLESInputStream);
  98 };
  99
 100 }  // namespace media
 101
 102 #endif  // MEDIA_AUDIO_ANDROID_OPENSLES_INPUT_H_