Mpeg2TS - estimate duration for video frames.

media/formats/mp2t/mp2t_stream_parser.cc

Index: media/formats/mp2t/mp2t_stream_parser.cc
diff --git a/media/formats/mp2t/mp2t_stream_parser.cc b/media/formats/mp2t/mp2t_stream_parser.cc
index 48497559d6a4bd502e9a72dba56eb29e71da2caf..444990165552da19c90ba16f9f654c8abf055fd8 100644
--- a/media/formats/mp2t/mp2t_stream_parser.cc
+++ b/media/formats/mp2t/mp2t_stream_parser.cc
@@ -157,8 +157,7 @@ Mp2tStreamParser::Mp2tStreamParser(bool sbr_in_mimetype)
     selected_audio_pid_(-1),
     selected_video_pid_(-1),
     is_initialized_(false),
-    segment_started_(false),
-    first_video_frame_in_segment_(true) {
+    segment_started_(false) {
 }
 
 Mp2tStreamParser::~Mp2tStreamParser() {
@@ -210,8 +209,6 @@ void Mp2tStreamParser::Flush() {
   // Note: does not need to invoke |end_of_segment_cb_| since flushing the
   // stream parser already involves the end of the current segment.
   segment_started_ = false;
-  first_video_frame_in_segment_ = true;
-  discarded_frames_dts_.clear();
 
   // Remove any bytes left in the TS buffer.
   // (i.e. any partial TS packet => less than 188 bytes).
@@ -505,7 +502,9 @@ void Mp2tStreamParser::OnEmitAudioBuffer(
       << " dts="
       << stream_parser_buffer->GetDecodeTimestamp().InMilliseconds()
       << " pts="
-      << stream_parser_buffer->timestamp().InMilliseconds();
+      << stream_parser_buffer->timestamp().InMilliseconds()
+      << " dur="
+      << stream_parser_buffer->duration().InMilliseconds();
   stream_parser_buffer->set_timestamp(
       stream_parser_buffer->timestamp() - time_offset_);
   stream_parser_buffer->SetDecodeTimestamp(
@@ -533,6 +532,8 @@ void Mp2tStreamParser::OnEmitVideoBuffer(
       << stream_parser_buffer->GetDecodeTimestamp().InMilliseconds()
       << " pts="
       << stream_parser_buffer->timestamp().InMilliseconds()
+      << " dur="
+      << stream_parser_buffer->duration().InMilliseconds()
       << " IsKeyframe="
       << stream_parser_buffer->IsKeyframe();
   stream_parser_buffer->set_timestamp(
@@ -540,29 +541,12 @@ void Mp2tStreamParser::OnEmitVideoBuffer(
   stream_parser_buffer->SetDecodeTimestamp(
       stream_parser_buffer->GetDecodeTimestamp() - time_offset_);
 
-  // Discard the incoming buffer:
-  // - if it is not associated with any config,
-  // - or if only non-key frames have been added to a new segment.
-  if (buffer_queue_chain_.empty() ||
-      (first_video_frame_in_segment_ && !stream_parser_buffer->IsKeyframe())) {
-    DVLOG(1) << "Discard video buffer:"
-             << " keyframe=" << stream_parser_buffer->IsKeyframe()
-             << " dts="
-             << stream_parser_buffer->GetDecodeTimestamp().InMilliseconds();
-    if (discarded_frames_dts_.empty() ||
-        discarded_frames_min_pts_ > stream_parser_buffer->timestamp()) {
-      discarded_frames_min_pts_ = stream_parser_buffer->timestamp();
-    }
-    discarded_frames_dts_.push_back(
-        stream_parser_buffer->GetDecodeTimestamp());
+  // Ignore the incoming buffer if it is not associated with any config.
+  if (buffer_queue_chain_.empty()) {
+    DVLOG(1) << "Ignoring video buffer with no corresponding video config";

[wolenetz, 2014/07/10 17:57:23]

If there has been no init segment prior to media segment, shouldn't parse error
occur? Should this clause trigger parse err? Furthermore, if there is a
non-empty chain, but it's back() has no video config, should we log or emit some
kind of error indication here, too?

[damienv1, 2014/07/10 18:34:52]

ditto.

     return;
   }
 
-  // Fill the gap created by frames that have been discarded.
-  if (!discarded_frames_dts_.empty())
-    FillVideoGap(stream_parser_buffer);
-
-  first_video_frame_in_segment_ = false;
   buffer_queue_chain_.back().video_queue.push_back(stream_parser_buffer);
 }
 
@@ -630,33 +614,5 @@ bool Mp2tStreamParser::EmitRemainingBuffers() {
   return true;
 }
 
-void Mp2tStreamParser::FillVideoGap(
-    const scoped_refptr<StreamParserBuffer>& stream_parser_buffer) {
-  DCHECK(!buffer_queue_chain_.empty());
-  DCHECK(!discarded_frames_dts_.empty());
-  DCHECK(stream_parser_buffer->IsKeyframe());
-
-  // PTS is interpolated between the min PTS of discarded frames
-  // and the PTS of the first valid buffer.
-  base::TimeDelta pts = discarded_frames_min_pts_;
-  base::TimeDelta pts_delta =
-      (stream_parser_buffer->timestamp() - pts) / discarded_frames_dts_.size();
-
-  while (!discarded_frames_dts_.empty()) {
-    scoped_refptr<StreamParserBuffer> frame =
-        StreamParserBuffer::CopyFrom(
-            stream_parser_buffer->data(),
-            stream_parser_buffer->data_size(),
-            stream_parser_buffer->IsKeyframe(),
-            stream_parser_buffer->type(),
-            stream_parser_buffer->track_id());
-    frame->SetDecodeTimestamp(discarded_frames_dts_.front());
-    frame->set_timestamp(pts);
-    buffer_queue_chain_.back().video_queue.push_back(frame);
-    pts += pts_delta;
-    discarded_frames_dts_.pop_front();
-  }
-}
-
 }  // namespace mp2t
 }  // namespace media