Encrypted Media: Add config change support in DecryptingAudioDecoder.

media/filters/decrypting_audio_decoder.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_FILTERS_DECRYPTING_AUDIO_DECODER_H_
 #define MEDIA_FILTERS_DECRYPTING_AUDIO_DECODER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/audio_decoder.h"
 #include "media/base/decryptor.h"
 #include "media/base/demuxer_stream.h"
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace media {
 
 class DecoderBuffer;
 class Decryptor;
 
 // Decryptor-based AudioDecoder implementation that can decrypt and decode
 // encrypted audio buffers and return decrypted and decompressed audio frames.
 // All public APIs and callbacks are trampolined to the |message_loop_| so
 // that no locks are required for thread safety.
-//
-// TODO(xhwang): For now, DecryptingAudioDecoder relies on the decryptor to do
-// both decryption and audio decoding. Add the path to use the decryptor for
-// decryption only and use other AudioDecoder implementations within
-// DecryptingAudioDecoder for audio decoding.
 class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
  public:
   DecryptingAudioDecoder(
       const scoped_refptr<base::MessageLoopProxy>& message_loop,
       const SetDecryptorReadyCB& set_decryptor_ready_cb);
 
   // AudioDecoder implementation.
   virtual void Initialize(const scoped_refptr<DemuxerStream>& stream,
                           const PipelineStatusCB& status_cb,
                           const StatisticsCB& statistics_cb) OVERRIDE;
   virtual void Read(const ReadCB& read_cb) OVERRIDE;
   virtual void Reset(const base::Closure& closure) OVERRIDE;
   virtual int bits_per_channel() OVERRIDE;
   virtual ChannelLayout channel_layout() OVERRIDE;
   virtual int samples_per_second() OVERRIDE;
 
  protected:
   virtual ~DecryptingAudioDecoder();
 
  private:
   // For a detailed state diagram please see this link: http://goo.gl/8jAok
   // TODO(xhwang): Add a ASCII state diagram in this file after this class
   // stabilizes.
   // TODO(xhwang): Update this diagram for DecryptingAudioDecoder.
   enum State {
     kUninitialized = 0,
     kDecryptorRequested,
     kPendingDecoderInit,
     kIdle,
+    kPendingConfigChange,
     kPendingDemuxerRead,
     kPendingDecode,
     kWaitingForKey,
     kDecodeFinished,
   };
 
   // Carries out the initialization operation scheduled by Initialize().
   void DoInitialize(const scoped_refptr<DemuxerStream>& stream,
                     const PipelineStatusCB& status_cb,
                     const StatisticsCB& statistics_cb);
 
   // Callback for DecryptorHost::RequestDecryptor().
   void SetDecryptor(Decryptor* decryptor);
 
-  // Callback for Decryptor::InitializeAudioDecoder().
+  // Callback for Decryptor::InitializeAudioDecoder() during initialization.
   void FinishInitialization(bool success);
 
+  // Callback for Decryptor::InitializeVideoDecoder() during config change.

[acolwell GONE FROM CHROMIUM, 2013/01/05 01:25:30]

s/Video/Audio

[xhwang, 2013/01/05 04:09:24]

Done.

+  void FinishConfigChange(bool success);
+
   // Carries out the buffer reading operation scheduled by Read().
   void DoRead(const ReadCB& read_cb);
 
   void ReadFromDemuxerStream();
 
   // Callback for DemuxerStream::Read().
   void DoDecryptAndDecodeBuffer(DemuxerStream::Status status,
                                 const scoped_refptr<DecoderBuffer>& buffer);
 
   void DecodePendingBuffer();
@@ skipping 60 matching lines @@
 
   base::TimeDelta output_timestamp_base_;
   int total_samples_decoded_;
 
   DISALLOW_COPY_AND_ASSIGN(DecryptingAudioDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_DECRYPTING_AUDIO_DECODER_H_