Add live mode detection in WebM MediaSource parser.

media/filters/ffmpeg_demuxer.cc

 // 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.
 
 #include "media/filters/ffmpeg_demuxer.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/base64.h"
@@ skipping 488 matching lines @@
 
 base::TimeDelta FFmpegDemuxer::GetStartTime() const {
   DCHECK(task_runner_->BelongsToCurrentThread());
   return start_time_;
 }
 
 base::Time FFmpegDemuxer::GetTimelineOffset() const {
   return timeline_offset_;
 }
 
+bool FFmpegDemuxer::IsLiveMode() const {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  return false;
+}
+
 void FFmpegDemuxer::AddTextStreams() {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   for (StreamVector::size_type idx = 0; idx < streams_.size(); ++idx) {
     FFmpegDemuxerStream* stream = streams_[idx];
     if (stream == NULL || stream->type() != DemuxerStream::TEXT)
       continue;
 
     TextKind kind = stream->GetTextKind();
     std::string title = stream->GetMetadata("title");
@@ skipping 155 matching lines @@
 
   if (format_context->duration != static_cast<int64_t>(AV_NOPTS_VALUE)) {
     // If there is a duration value in the container use that to find the
     // maximum between it and the duration from A/V streams.
     const AVRational av_time_base = {1, AV_TIME_BASE};
     max_duration =
         std::max(max_duration,
                  ConvertFromTimeBase(av_time_base, format_context->duration));
   } else {
     // The duration is unknown, in which case this is likely a live stream.
     max_duration = kInfiniteDuration();

[acolwell GONE FROM CHROMIUM, 2014/04/24 21:14:16]

We should probably reflect this assumption via IsLiveMode() as well.

[Sergey Ulanov, 2014/04/24 23:17:45]

Done. For consistency with the WebM parser it checks both timeline_offset_ and
max_duration to detect live mode.

   }
 
   // Some demuxers, like WAV, do not put timestamps on their frames. We
   // assume the the start time is 0.
   if (start_time_ == kNoTimestamp())
     start_time_ = base::TimeDelta();
 
   // MPEG-4 B-frames cause grief for a simple container like AVI. Enable PTS
   // generation so we always get timestamps, see http://crbug.com/169570
   if (strcmp(format_context->iformat->name, "avi") == 0)
@@ skipping 307 matching lines @@
   }
   for (size_t i = 0; i < buffered.size(); ++i)
     host_->AddBufferedTimeRange(buffered.start(i), buffered.end(i));
 }
 
 void FFmpegDemuxer::OnDataSourceError() {
   host_->OnDemuxerError(PIPELINE_ERROR_READ);
 }
 
 }  // namespace media