media: Discard the previous decoder immediately on fallback

media/filters/decoder_stream.h

 // Copyright 2014 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_DECODER_STREAM_H_
 #define MEDIA_FILTERS_DECODER_STREAM_H_
 
 #include <deque>
 #include <list>
 #include <memory>
@@ skipping 94 matching lines @@
 
   // Allows callers to register for notification of config changes; this is
   // called immediately after receiving the 'kConfigChanged' status from the
   // DemuxerStream, before any action is taken to handle the config change.
   typedef base::Closure ConfigChangeObserverCB;
   void set_config_change_observer(
       const ConfigChangeObserverCB& config_change_observer) {
     config_change_observer_cb_ = config_change_observer;
   }
 
-  const Decoder* get_previous_decoder_for_testing() const {
-    return previous_decoder_.get();
-  }
-
   int get_pending_buffers_size_for_testing() const {
     return pending_buffers_.size();
   }
 
   int get_fallback_buffers_size_for_testing() const {
     return fallback_buffers_.size();
   }
 
  private:
   enum State {
@@ skipping 69 matching lines @@
   base::Closure reset_cb_;
 
   DemuxerStream* stream_;
 
   CdmContext* cdm_context_;
 
   std::unique_ptr<DecoderSelector<StreamType>> decoder_selector_;
 
   std::unique_ptr<Decoder> decoder_;
 
-  // When falling back from H/W decoding to S/W decoding, destructing the
-  // GpuVideoDecoder too early results in black frames being displayed.
-  // |previous_decoder_| is used to keep it alive.  It is destroyed once we've
-  // decoded at least media::limits::kMaxVideoFrames frames after fallback.
-  int decoded_frames_since_fallback_;
-  std::unique_ptr<Decoder> previous_decoder_;
+  // Whether |decoder_| has produced a frame yet. Reset on fallback.
+  bool decoder_produced_a_frame_;
 
   std::unique_ptr<DecryptingDemuxerStream> decrypting_demuxer_stream_;
 
   ConfigChangeObserverCB config_change_observer_cb_;
 
   // An end-of-stream buffer has been sent for decoding, no more buffers should
   // be sent for decoding until it completes.
   // TODO(sandersd): Turn this into a State. http://crbug.com/408316
   bool decoding_eos_;
 
@@ skipping 37 matching lines @@
 
 template <>
 int DecoderStream<DemuxerStream::AUDIO>::GetMaxDecodeRequests() const;
 
 typedef DecoderStream<DemuxerStream::VIDEO> VideoFrameStream;
 typedef DecoderStream<DemuxerStream::AUDIO> AudioBufferStream;
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_DECODER_STREAM_H_