Fire CanPlayThrough immediately for local and streaming media files

media/base/download_rate_monitor.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.
 
 #ifndef MEDIA_BASE_DOWNLOAD_RATE_MONITOR_H_
 #define MEDIA_BASE_DOWNLOAD_RATE_MONITOR_H_
 
 #include <deque>
 
 #include "base/bind.h"
@@ skipping 24 matching lines @@
   void SetBufferedBytes(int64 buffered_bytes, const base::Time& timestamp);
 
   // Notifies the monitor when the media file has paused or continued
   // downloading data.
   void SetNetworkActivity(bool is_downloading_data);
 
   void set_total_bytes(int64 total_bytes) { total_bytes_ = total_bytes; }
 
   void set_loaded(bool loaded) { loaded_ = loaded; }
 
+  void set_media_stream(bool media_stream) { media_stream_ = media_stream; }
+
+  void set_streaming(bool streaming) { streaming_ = streaming; }
+
   // Stop monitoring download rate. This does not discard previously learned
   // information, but it will no longer factor incoming information into its
   // canplaythrough estimation.
   void Stop();
 
   // Resets monitor to uninitialized state.
   void Reset();
 
  private:
   // Represents a point in time in which the media was buffering data.
@@ skipping 85 matching lines @@
   // True if the media file is a fully loaded source, e.g. file:// protocol.
   bool loaded_;
 
   // Bitrate of the media file, 0 if unknown.
   int bitrate_;
 
   // True if the monitor has not yet started or has been stopped, false
   // otherwise.
   bool stopped_;
 
+  // True if the data source is a media stream, e.g. video input from a local
+  // capture device, false otherwise.
+  bool media_stream_;
+
+  // True if the data source is a streaming source, false otherwise.
+  bool streaming_;

[scherkus (not reviewing), 2011/11/23 01:59:44]

wouldn't setting streaming=true for web cams also work w/o introducing the
concept of a media stream?

[vrk (LEFT CHROMIUM), 2011/11/23 21:29:45]

There were 2 reasons why I introduced media stream:

1) Technically there is a slight difference in their definitions, the most
important difference being that a local webcam stream does not download data,
whereas every other stream type does. In terms of DownloadRateMonitor, this
means a local webcam stream *must* immediately fire CanPlayThrough, but firing
CanPlayThrough immediately for other types of streams is a design decision.

2) The SetStreaming method in PipelineImpl is part of the FilterHost interface,
meaning I had to add a differently named method to the Pipeline interface anyway
to get the WebMediaPlayerImpl -> PipelineImpl communication. So I figured I may
as well be specific.

I agree it's not ideal :/ so I'm willing to change.

Btw, in the currently checked-in code, can MediaStream be anything but a local
webcam feed? (I know the spec says it can be a remote source, but is that
implemented and checked in?) If it's always a local source, I could at least
rename things to make things clearer.

+
   DISALLOW_COPY_AND_ASSIGN(DownloadRateMonitor);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_DOWNLOAD_RATE_MONITOR_H_