Always use 48kHz for OPUS decoding.

media/formats/webm/webm_audio_client.cc

 // Copyright 2014 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/formats/webm/webm_audio_client.h"
 
 #include "media/base/audio_decoder_config.h"
 #include "media/base/channel_layout.h"
 #include "media/formats/webm/webm_constants.h"
 
@@ skipping 40 matching lines @@
 
   if (channel_layout == CHANNEL_LAYOUT_UNSUPPORTED) {
     MEDIA_LOG(log_cb_) << "Unsupported channel count " << channels_;
     return false;
   }
 
   int samples_per_second = samples_per_second_;
   if (output_samples_per_second_ > 0)
     samples_per_second = output_samples_per_second_;
 
+  // Always use 48kHz for OPUS.  See the "Input Sample Rate" section of the
+  // spec: http://tools.ietf.org/html/draft-terriberry-oggopus-01#page-11
+  if (audio_codec == kCodecOpus)
+    samples_per_second = 48000;
+
   const uint8* extra_data = NULL;
   size_t extra_data_size = 0;
   if (codec_private.size() > 0) {
     extra_data = &codec_private[0];
     extra_data_size = codec_private.size();
   }
 
   // Convert |codec_delay| from nanoseconds into frames.
   int codec_delay_in_frames = 0;
   if (codec_delay != -1) {
@@ skipping 53 matching lines @@
     MEDIA_LOG(log_cb_) << "Multiple values for id " << std::hex << id
                        << " specified (" << *dst << " and " << val << ")";
     return false;
   }
 
   *dst = val;
   return true;
 }
 
 }  // namespace media