Fire CanPlayThrough immediately for local and streaming media files

media/base/filters.h

 // Copyright (c) 2011 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.
 
 // Filters are connected in a strongly typed manner, with downstream filters
 // always reading data from upstream filters.  Upstream filters have no clue
 // who is actually reading from them, and return the results via callbacks.
 //
 //                         DemuxerStream(Video) <- VideoDecoder <- VideoRenderer
 // DataSource <- Demuxer <
@@ skipping 139 matching lines @@
   // Returns true if we are performing streaming. In this case seeking is
   // not possible.
   virtual bool IsStreaming() = 0;
 
   // Alert the DataSource that the video preload value has been changed.
   virtual void SetPreload(Preload preload) = 0;
 
   // Notify the DataSource of the bitrate of the media.
   // Values of |bitrate| <= 0 are invalid and should be ignored.
   virtual void SetBitrate(int bitrate) = 0;
+
+  // Returns true if the data source is from a local file or stream (such as a
+  // webcam stream), false otherwise.
+  virtual bool IsLocalSource() = 0;

[acolwell GONE FROM CHROMIUM, 2011/11/30 19:26:11]

I wonder if adding this method is needed since the implementations for the 2
DataSource implementations are very similar and are both scheme based. 

What do you think about adding the URL scheme checks to FFmpegDemuxerFactory and
just pass the local_source value to FFmpegDemuxer's constructor? I believe this
should work since I don't think it is valid for HTTP to redirect to file: or
data: URLs

[vrk (LEFT CHROMIUM), 2011/12/01 02:11:35]

Yeah, that's what I was thinking too. Done.

 };
 
 class MEDIA_EXPORT VideoDecoder : public Filter {
  public:
   // Initialize a VideoDecoder with the given DemuxerStream, executing the
   // callback upon completion.
   // stats_callback is used to update global pipeline statistics.
   //
   // TODO(scherkus): switch to PipelineStatus callback.
   virtual void Initialize(DemuxerStream* stream, const base::Closure& callback,
@@ skipping 98 matching lines @@
 
   // Resumes playback after underflow occurs.
   // |buffer_more_audio| is set to true if you want to increase the size of the
   // decoded audio buffer.
   virtual void ResumeAfterUnderflow(bool buffer_more_audio) = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_FILTERS_H_