Fix muted audio when playback rate != 1.0 or 0.0

media/filters/audio_renderer_base.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.
 
 // AudioRendererBase takes care of the tricky queuing work and provides simple
 // methods for subclasses to peek and poke at audio data.  In addition to
 // AudioRenderer interface methods this classes doesn't implement, subclasses
 // must also implement the following methods:
 //   OnInitialized
 //   OnStop
@@ skipping 55 matching lines @@
   // Method called by FillBuffer() when it finds that it reached end of stream.
   // FillBuffer() cannot immediately signal end of stream event because browser
   // may have buffered data.
   virtual void OnRenderEndOfStream() = 0;
 
   // Callback from the audio decoder delivering decoded audio samples.
   void DecodedAudioReady(scoped_refptr<Buffer> buffer);
 
   // Fills the given buffer with audio data by delegating to its |algorithm_|.
   // FillBuffer() also takes care of updating the clock. Returns the number of
-  // bytes copied into |dest|, which may be less than or equal to |len|.
+  // frames copied into |dest|, which may be less than or equal to
+  // |requested_frames|.
   //
-  // If this method is returns less bytes than |len| (including zero), it could
+  // If this method returns fewer frames than |requested_frames|, it could
   // be a sign that the pipeline is stalled or unable to stream the data fast
   // enough.  In such scenarios, the callee should zero out unused portions
   // of their buffer to playback silence.
   //
   // FillBuffer() updates the pipeline's playback timestamp. If FillBuffer() is
   // not called at the same rate as audio samples are played, then the reported
   // timestamp in the pipeline will be ahead of the actual audio playback. In
   // this case |playback_delay| should be used to indicate when in the future
   // should the filled buffer be played. If FillBuffer() is called as the audio
   // hardware plays the buffer, then |playback_delay| should be zero.
   //
   // FillBuffer() calls OnRenderEndOfStream() when it reaches end of stream.
   // It is responsibility of derived class to provide implementation of
   // OnRenderEndOfStream() that calls SignalEndOfStream() when all the hardware
   // buffers become empty (i.e. when all the data written to the device has
   // been played).
   //
   // Safe to call on any thread.
   uint32 FillBuffer(uint8* dest,
-                    uint32 len,
+                    uint32 requested_frames,
                     const base::TimeDelta& playback_delay);
 
   // Called by OnRenderEndOfStream() or some callback scheduled by derived class
   // to signal end of stream.
   void SignalEndOfStream();
 
   // Get/Set the playback rate of |algorithm_|.
   virtual void SetPlaybackRate(float playback_rate) OVERRIDE;
   virtual float GetPlaybackRate();
 
@@ skipping 28 matching lines @@
     kStopped,
     kUnderflow,
     kRebuffering,
   };
   State state_;
 
   // Keep track of our outstanding read to |decoder_|.
   bool pending_read_;
 
   // Keeps track of whether we received and rendered the end of stream buffer.
-  bool recieved_end_of_stream_;
+  bool received_end_of_stream_;
   bool rendered_end_of_stream_;
 
   // Audio time at end of last call to FillBuffer().
   // TODO(ralphl): Update this value after seeking.
   base::TimeDelta last_fill_buffer_time_;
 
   // Filter callbacks.
   base::Closure pause_callback_;
   FilterStatusCB seek_cb_;
 
   base::Closure underflow_callback_;
 
   AudioTimeCB audio_time_cb_;
 
   base::TimeDelta seek_timestamp_;
 
+  uint32 bytes_per_frame_;
+
   AudioDecoder::ReadCB read_cb_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererBase);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_AUDIO_RENDERER_BASE_H_