2 files changed, 23 insertions, 9 deletions

diff --git a/media/filters/ffmpeg_audio_decoder.cc b/media/filters/ffmpeg_audio_decoder.cc
index 8ee6fa8..6f4f5e1 100644
--- a/media/filters/ffmpeg_audio_decoder.cc
+++ b/media/filters/ffmpeg_audio_decoder.cc
@@ -2,8 +2,9 @@
 // source code is governed by a BSD-style license that can be found in the
 // LICENSE file.
 
-#include "media/base/data_buffer.h"
 #include "media/filters/ffmpeg_audio_decoder.h"
+
+#include "media/base/data_buffer.h"
 #include "media/filters/ffmpeg_common.h"
 #include "media/filters/ffmpeg_demuxer.h"
 
@@ -73,16 +74,15 @@ bool FFmpegAudioDecoder::OnInitialize(DemuxerStream* demuxer_stream) {
   return true;
 }
 
+void FFmpegAudioDecoder::OnSeek(base::TimeDelta time) {
+  avcodec_flush_buffers(codec_context_);
+  estimated_next_timestamp_ = base::TimeDelta();
+}
+
 void FFmpegAudioDecoder::OnStop() {
 }
 
 void FFmpegAudioDecoder::OnDecode(Buffer* input) {
-  // Check for discontinuous buffer. If we receive a discontinuous buffer here,
-  // flush the internal buffer of FFmpeg.
-  if (input->IsDiscontinuous()) {
-    avcodec_flush_buffers(codec_context_);
-  }
-
   // Due to FFmpeg API changes we no longer have const read-only pointers.
   AVPacket packet;
   av_init_packet(&packet);
@@ -120,8 +120,17 @@ void FFmpegAudioDecoder::OnDecode(Buffer* input) {
       result_buffer->SetDuration(input->GetDuration());
     }
 
-    // Copy over the timestamp.
-    result_buffer->SetTimestamp(input->GetTimestamp());
+    // Use our estimate for the timestamp if |input| does not have one.
+    // Otherwise, copy over the timestamp.
+    if (input->GetTimestamp().InMicroseconds() == 0) {
+      result_buffer->SetTimestamp(estimated_next_timestamp_);
+    } else {
+      result_buffer->SetTimestamp(input->GetTimestamp());
+    }
+
+    // Update our estimated timestamp for the next packet.
+    estimated_next_timestamp_ = result_buffer->GetTimestamp() +
+        result_buffer->GetDuration();
 
     EnqueueResult(result_buffer);
     return;
diff --git a/media/filters/ffmpeg_audio_decoder.h b/media/filters/ffmpeg_audio_decoder.h
index 0ef6119..f7adc33 100644
--- a/media/filters/ffmpeg_audio_decoder.h
+++ b/media/filters/ffmpeg_audio_decoder.h
@@ -26,6 +26,8 @@ class FFmpegAudioDecoder : public DecoderBase<AudioDecoder, Buffer> {
  protected:
   virtual bool OnInitialize(DemuxerStream* demuxer_stream);
 
+  virtual void OnSeek(base::TimeDelta time);
+
   virtual void OnStop();
 
   virtual void OnDecode(Buffer* input);
@@ -43,6 +45,9 @@ class FFmpegAudioDecoder : public DecoderBase<AudioDecoder, Buffer> {
   // is initialized in OnInitialize().
   AVCodecContext* codec_context_;
 
+  // Estimated timestamp for next packet. Useful for packets without timestamps.
+  base::TimeDelta estimated_next_timestamp_;
+
   // Data buffer to carry decoded raw PCM samples. This buffer is created by
   // av_malloc() and is used throughout the lifetime of this class.
   scoped_ptr_malloc<uint8, ScopedPtrAVFree> output_buffer_;