// Copyright 2015 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_FORMATS_MP4_BITSTREAM_CONVERTER_H_
#define MEDIA_FORMATS_MP4_BITSTREAM_CONVERTER_H_

#include <stdint.h>

#include <vector>

#include "base/memory/ref_counted.h"

namespace media {

struct SubsampleEntry;

namespace mp4 {

// BitstreamConverter provides a unified interface for performing some common
// bitstream conversions (e.g. H.264 MP4 bitstream to Annex B, and elementary
// AAC stream to ADTS).
class BitstreamConverter
    : public base::RefCountedThreadSafe<BitstreamConverter> {
 public:
  // Converts a single frame/buffer |frame_buf| into the output format.
  // Returns true iff the conversion was successful.
  // |frame_buf| is an input/output parameter, it contains input frame data and
  // contains converted output data if conversion was successful.
  // |is_keyframe| indicates whether it's a key frame or not.
  // |subsamples| is an input/output parameter that contains CENC subsample
  // information. The conversion code should |subsamples| to determine if parts
  // of input frame are encrypted and should update |subsamples| if necessary,
  // to make sure it correctly describes the converted output frame. See
  // SubsampleEntry definition in media/base/decrypt_config.h for more info.
  virtual bool ConvertFrame(std::vector<uint8_t>* frame_buf,
                            bool is_keyframe,
                            std::vector<SubsampleEntry>* subsamples) const = 0;

 protected:
  friend class base::RefCountedThreadSafe<BitstreamConverter>;
  virtual ~BitstreamConverter();
};

}  // namespace mp4
}  // namespace media

#endif  // MEDIA_FORMATS_MP4_BITSTREAM_CONVERTER_H_