Added aac bitstream converter

media/filters/ffmpeg_bitstream_converter.h

+// 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.
+
+#ifndef MEDIA_FILTERS_FFMPEG_BITSTREAM_CONVERTER_H_
+#define MEDIA_FILTERS_FFMPEG_BITSTREAM_CONVERTER_H_
+
+#include "base/basictypes.h"
+#include "media/base/media_export.h"
+
+struct AVPacket;
+
+namespace media {
+
+// Interface for classes that allow reformating of FFmpeg bitstreams
+class MEDIA_EXPORT FFmpegBitstreamConverter {
+ public:
+  virtual ~FFmpegBitstreamConverter() {};
+
+  // Reads the data in packet, and then overwrites this data with the
+  // converted version of packet
+  //
+  // Returns false if conversion failed. In this case, |packet| should not be
+  // changed.
+  virtual bool ConvertPacket(AVPacket* packet) = 0;
+};
+
+}  // namespace media
+
+#endif  // MEDIA_FILTERS_FFMPEG_BITSTREAM_CONVERTER_H_