Pass delay and timestamp to AudioSourceCallback::OnMoreData.

media/audio/audio_io.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_AUDIO_AUDIO_IO_H_
 #define MEDIA_AUDIO_AUDIO_IO_H_
 
 #include <stdint.h>
 
+#include "base/time/time.h"
 #include "media/base/audio_bus.h"
 
 // Low-level audio output support. To make sound there are 3 objects involved:
 // - AudioSource : produces audio samples on a pull model. Implements
 //   the AudioSourceCallback interface.
 // - AudioOutputStream : uses the AudioSource to render audio on a given
 //   channel, format and sample frequency configuration. Data from the
 //   AudioSource is delivered in a 'pull' model.
 // - AudioManager : factory for the AudioOutputStream objects, manager
 //   of the hardware resources and mixer control.
@@ skipping 32 matching lines @@
 class MEDIA_EXPORT AudioOutputStream {
  public:
   // Audio sources must implement AudioSourceCallback. This interface will be
   // called in a random thread which very likely is a high priority thread. Do
   // not rely on using this thread TLS or make calls that alter the thread
   // itself such as creating Windows or initializing COM.
   class MEDIA_EXPORT AudioSourceCallback {
    public:
     virtual ~AudioSourceCallback() {}
 
-    // Provide more data by fully filling |dest|.  The source will return
-    // the number of frames it filled.  |total_bytes_delay| contains current
-    // number of bytes of delay buffered by the AudioOutputStream.
-    // |frames_skipped| contains the number of frames skipped by the consumer.
-    virtual int OnMoreData(AudioBus* dest,
-                           uint32_t total_bytes_delay,
-                           uint32_t frames_skipped) = 0;
+    // Provide more data by fully filling |dest|. The source will return the
+    // number of frames it filled. |target_playout_time| is the time when the
+    // first sample added to |dest| is expected to be played and should equal
+    // the audio output delay added to the time when it was calculated. It may
+    // be used to determine when to make adjustments to keep audio output
+    // synchronized, such as adjusting the media clock rate or adding or
+    // dropping frames. The accuracy of |target_playout_time| may vary depending
+    // on the platform and implementation. |prior_frames_skipped| is the number
+    // of frames skipped by the consumer.
+    virtual int OnMoreData(base::TimeTicks target_playout_time,
+                           int prior_frames_skipped,
+                           AudioBus* dest) = 0;
 
     // There was an error while playing a buffer. Audio source cannot be
     // destroyed yet. No direct action needed by the AudioStream, but it is
     // a good place to stop accumulating sound data since is is likely that
     // playback will not continue.
     virtual void OnError(AudioOutputStream* stream) = 0;
   };
 
   virtual ~AudioOutputStream() {}
 
@@ skipping 28 matching lines @@
  public:
   class MEDIA_EXPORT AudioInputCallback {
    public:
     // Called by the audio recorder when a full packet of audio data is
     // available. This is called from a special audio thread and the
     // implementation should return as soon as possible.
     // TODO(henrika): should be pure virtual when old OnData() is phased out.
     virtual void OnData(AudioInputStream* stream,
                         const AudioBus* source,
                         uint32_t hardware_delay_bytes,
-                        double volume){};
+                        double volume) {}
 
     // TODO(henrika): don't use; to be removed.
     virtual void OnData(AudioInputStream* stream,
                         const uint8_t* src,
                         uint32_t size,
                         uint32_t hardware_delay_bytes,
-                        double volume){};
+                        double volume) {}
 
     // There was an error while recording audio. The audio sink cannot be
     // destroyed yet. No direct action needed by the AudioInputStream, but it
     // is a good place to stop accumulating sound data since is is likely that
     // recording will not continue.
     virtual void OnError(AudioInputStream* stream) = 0;
 
    protected:
     virtual ~AudioInputCallback() {}
   };
@@ skipping 33 matching lines @@
   // Returns the Automatic Gain Control (AGC) state.
   virtual bool GetAutomaticGainControl() = 0;
 
   // Returns the current muting state for the microphone.
   virtual bool IsMuted() = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_IO_H_