Add WebMediaPlayer::timelineOffset() support to WebMediaPlayerImpl.

media/filters/ffmpeg_demuxer.cc

Index: media/filters/ffmpeg_demuxer.cc
diff --git a/media/filters/ffmpeg_demuxer.cc b/media/filters/ffmpeg_demuxer.cc
index de1968afc43d200f86f0eeb3791621ce72d54d72..cbee00c65a0ebd4cf05170eae2bc3ade990eab35 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -14,6 +14,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/metrics/sparse_histogram.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/sys_byteorder.h"
@@ -34,6 +35,38 @@
 
 namespace media {
 
+static base::Time ExtractTimelineOffset(AVFormatContext* format_context) {

[scherkus (not reviewing), 2014/04/15 00:53:40]

parsing code without tests makes me nervous

how about moving this to media/ffmpeg/ffmpeg_common.h and adding tests?

perhaps something like:
base::Time ConvertToTime(const char* ffmpeg_utc) { ... }

then you can keep the demuxer-related logic (e.g,. checking for webm/matroska,
getting the dictionary stuff) in ffmpeg_demuxer.cc

[acolwell GONE FROM CHROMIUM, 2014/04/16 01:01:08]

Done.

+  if (strstr(format_context->iformat->name, "webm") ||
+      strstr(format_context->iformat->name, "matroska")) {
+    const AVDictionaryEntry* entry =
+        av_dict_get(format_context->metadata, "creation_time", NULL, 0);
+
+    // Convert ffmpeg UTC representation (YYYY-MM-DD HH:MM:SS) to base::Time.

[scherkus (not reviewing), 2014/04/15 00:53:40]

s/ffmpeg/FFmpeg/

[acolwell GONE FROM CHROMIUM, 2014/04/16 01:01:08]

Done.

+    std::vector<std::string> fields;
+    std::vector<std::string> date_fields;
+    std::vector<std::string> time_fields;
+    base::Time::Exploded exploded;
+    exploded.millisecond = 0;
+
+    // TODO: Update this parsing code when FFmpeg returns sub-second

[scherkus (not reviewing), 2014/04/15 00:53:40]

TODO(acolwell)?

[acolwell GONE FROM CHROMIUM, 2014/04/16 01:01:08]

Done.

+    // information.
+    if (entry != NULL && entry->value != NULL &&
+        (Tokenize(entry->value, " ", &fields) == 2) &&
+        (Tokenize(fields[0], "-", &date_fields) == 3) &&
+        (Tokenize(fields[1], ":", &time_fields) == 3) &&
+        base::StringToInt(date_fields[0], &exploded.year) &&
+        base::StringToInt(date_fields[1], &exploded.month) &&
+        base::StringToInt(date_fields[2], &exploded.day_of_month) &&
+        base::StringToInt(time_fields[0], &exploded.hour) &&
+        base::StringToInt(time_fields[1], &exploded.minute) &&
+        base::StringToInt(time_fields[2], &exploded.second)) {
+      return base::Time::FromUTCExploded(exploded);
+    }
+  }
+
+  return base::Time();
+}
+
 //
 // FFmpegDemuxerStream
 //
@@ -486,6 +519,10 @@ base::TimeDelta FFmpegDemuxer::GetStartTime() const {
   return start_time_;
 }
 
+base::Time FFmpegDemuxer::GetWallclockTimelineOffset() const {
+  return wallclock_timeline_offset_;
+}
+
 void FFmpegDemuxer::AddTextStreams() {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
@@ -674,6 +711,8 @@ void FFmpegDemuxer::OnFindStreamInfoDone(const PipelineStatusCB& status_cb,
   if (strcmp(format_context->iformat->name, "avi") == 0)
     format_context->flags |= AVFMT_FLAG_GENPTS;
 
+  wallclock_timeline_offset_ = ExtractTimelineOffset(format_context);
+
   // Good to go: set the duration and bitrate and notify we're done
   // initializing.
   host_->SetDuration(max_duration);