media: Opus support for WebM in Media Source

media/base/audio_decoder_config.h

 // 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.
 
 #ifndef MEDIA_BASE_AUDIO_DECODER_CONFIG_H_
 #define MEDIA_BASE_AUDIO_DECODER_CONFIG_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/time/time.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
 #include "media/base/sample_format.h"
 
 namespace media {
 
 enum AudioCodec {
   // These values are histogrammed over time; do not change their ordinal
   // values.  When deleting a codec replace it with a dummy value; when adding a
   // codec, do so at the bottom before kAudioCodecMax.
@@ skipping 35 matching lines @@
                      ChannelLayout channel_layout, int samples_per_second,
                      const uint8* extra_data, size_t extra_data_size,
                      bool is_encrypted);
 
   ~AudioDecoderConfig();
 
   // Resets the internal state of this object.
   void Initialize(AudioCodec codec, SampleFormat sample_format,
                   ChannelLayout channel_layout, int samples_per_second,
                   const uint8* extra_data, size_t extra_data_size,
-                  bool is_encrypted, bool record_stats);
+                  bool is_encrypted, bool record_stats,
+                  base::TimeDelta seek_pre_roll,

[acolwell GONE FROM CHROMIUM, 2013/09/03 20:14:01]

nit: s/seek_pre_roll/seek_preroll/ here and everywhere else.

[vignesh, 2013/09/03 22:43:03]

Done.

+                  base::TimeDelta codec_delay);
 
   // Returns true if this object has appropriate configuration values, false
   // otherwise.
   bool IsValidConfig() const;
 
   // Returns true if all fields in |config| match this config.
   // Note: The contents of |extra_data_| are compared not the raw pointers.
   bool Matches(const AudioDecoderConfig& config) const;
 
   AudioCodec codec() const { return codec_; }
   int bits_per_channel() const { return bytes_per_channel_ * 8; }
   int bytes_per_channel() const { return bytes_per_channel_; }
   ChannelLayout channel_layout() const { return channel_layout_; }
   int samples_per_second() const { return samples_per_second_; }
   SampleFormat sample_format() const { return sample_format_; }
   int bytes_per_frame() const { return bytes_per_frame_; }
+  base::TimeDelta seek_pre_roll() const { return seek_pre_roll_; }
+  base::TimeDelta codec_delay() const { return codec_delay_; }
 
   // Optional byte data required to initialize audio decoders such as Vorbis
   // codebooks.
   const uint8* extra_data() const {
     return extra_data_.empty() ? NULL : &extra_data_[0];
   }
   size_t extra_data_size() const { return extra_data_.size(); }
 
   // Whether the audio stream is potentially encrypted.
   // Note that in a potentially encrypted audio stream, individual buffers
   // can be encrypted or not encrypted.
   bool is_encrypted() const { return is_encrypted_; }
 
  private:
   AudioCodec codec_;
   SampleFormat sample_format_;
   int bytes_per_channel_;
   ChannelLayout channel_layout_;
   int samples_per_second_;
   int bytes_per_frame_;
   std::vector<uint8> extra_data_;
   bool is_encrypted_;
 
+  // |seek_pre_roll_| is the duration in nanoseconds of the data that the

[acolwell GONE FROM CHROMIUM, 2013/09/03 20:14:01]

nit: s/nanoseconds//

[vignesh, 2013/09/03 22:43:03]

Done.

+  // decoder must decode before the decoded data is valid.
+  base::TimeDelta seek_pre_roll_;
+
+  // |codec_delay_| is the overall delay overhead in nanoseconds added by the

[acolwell GONE FROM CHROMIUM, 2013/09/03 20:14:01]

ditto

[vignesh, 2013/09/03 22:43:03]

Done.

+  // codec while encoding. This value should be subtracted from each block's
+  // timestamp to get the actual timestamp.
+  base::TimeDelta codec_delay_;
+
   // Not using DISALLOW_COPY_AND_ASSIGN here intentionally to allow the compiler
   // generated copy constructor and assignment operator. Since the extra data is
   // typically small, the performance impact is minimal.
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_DECODER_CONFIG_H_