Don't double correct for discarded codec delay frames.

media/filters/opus_audio_decoder.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/opus_audio_decoder.h"
 
 #include <cmath>
 
 #include "base/single_thread_task_runner.h"
 #include "base/sys_byteorder.h"
@@ skipping 271 matching lines @@
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   opus_multistream_decoder_ctl(opus_decoder_, OPUS_RESET_STATE);
   ResetTimestampState();
   task_runner_->PostTask(FROM_HERE, closure);
 }
 
 void OpusAudioDecoder::Stop() {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
+  if (!opus_decoder_)
+    return;
+
   opus_multistream_decoder_ctl(opus_decoder_, OPUS_RESET_STATE);
   ResetTimestampState();
   CloseDecoder();
 }
 
 OpusAudioDecoder::~OpusAudioDecoder() {}
 
 void OpusAudioDecoder::DecodeBuffer(
     const scoped_refptr<DecoderBuffer>& input,
     const DecodeCB& decode_cb) {
@@ skipping 89 matching lines @@
     return false;
 
   if (config_.codec_delay() <= 0) {
     DLOG(ERROR) << "Invalid file. Incorrect value for codec delay: "
                 << config_.codec_delay();
     return false;
   }
 
   if (config_.codec_delay() != opus_extra_data.skip_samples) {
     DLOG(ERROR) << "Invalid file. Codec Delay in container does not match the "
-                << "value in Opus Extra Data.";
+                << "value in Opus Extra Data. " << config_.codec_delay()
+                << " vs " << opus_extra_data.skip_samples;
     return false;
   }
 
   uint8 channel_mapping[kMaxVorbisChannels] = {0};
   memcpy(&channel_mapping,
          kDefaultOpusChannelLayout,
          kMaxChannelsWithDefaultLayout);
 
   if (channel_count > kMaxChannelsWithDefaultLayout) {
     RemapOpusChannelLayout(opus_extra_data.stream_map,
@@ skipping 72 matching lines @@
                 << " timestamp: " << input->timestamp().InMicroseconds()
                 << " us, duration: " << input->duration().InMicroseconds()
                 << " us, packet size: " << input->data_size() << " bytes with"
                 << " status: " << opus_strerror(frames_decoded);
     return false;
   }
 
   if (output_timestamp_helper_->base_timestamp() == kNoTimestamp() &&
       !input->end_of_stream()) {
     DCHECK(input->timestamp() != kNoTimestamp());
-    // Adjust the timestamp helper so the base timestamp is corrected for frames
-    // dropped due to codec delay.
     output_timestamp_helper_->SetBaseTimestamp(input->timestamp());
-    output_timestamp_helper_->SetBaseTimestamp(
-        input->timestamp() -
-        output_timestamp_helper_->GetFrameDuration(config_.codec_delay()));
   }
 
   // Trim off any extraneous allocation.
   DCHECK_LE(frames_decoded, output_buffer->get()->frame_count());
   const int trim_frames = output_buffer->get()->frame_count() - frames_decoded;
   if (trim_frames > 0)
     output_buffer->get()->TrimEnd(trim_frames);
 
   // Handle frame discard and trimming.
   int frames_to_output = frames_decoded;
@@ skipping 28 matching lines @@
 
   // Assign timestamp and duration to the buffer.
   output_buffer->get()->set_timestamp(output_timestamp_helper_->GetTimestamp());
   output_buffer->get()->set_duration(
       output_timestamp_helper_->GetFrameDuration(frames_to_output));
   output_timestamp_helper_->AddFrames(frames_to_output);
   return true;
 }
 
 }  // namespace media