include/webmmuxcontext.hpp

// Copyright (c) 2010 The WebM project authors. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the LICENSE file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS.  All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.

#ifndef WEBMMUXCONTEXT_HPP
#define WEBMMUXCONTEXT_HPP

#include <list>
#include <string>
#include "webmmuxstreamvideo.hpp"
#include "webmmuxstreamaudio.hpp"
#include "webmmuxebmlio.hpp"

namespace webmmux
{
class Context
{
  Context(const Context&);
  Context& operator=(const Context&);

public:
  File m_file;
  std::wstring m_writing_app;

  Context();
  ~Context();

  void GetVersion(int *major, int *minor, int *build, int *revision);

  void SetVideoStream(StreamVideo* pVideo);

  // TODO: this needs to liberalized to handle multiple audio streams.
  void SetAudioStream(StreamAudio* pAudio);

  void Open(EbmlStreamInterface* pStream);
  void Close();

  void NotifyVideoFrame(StreamVideo* pVideo, StreamVideo::VideoFrame* pFrame);
  int NotifyVideoEOS(StreamVideo* pVideo);
  void FlushVideo(StreamVideo* pVideo);
  bool WaitVideo() const;

  void NotifyAudioFrame(StreamAudio* pAudio, StreamAudio::AudioFrame* pFrame);
  int NotifyAudioEOS(StreamAudio* pAudio);
  void FlushAudio(StreamAudio* pAudio);
  bool WaitAudio() const;

  unsigned long GetTimecodeScale() const;
  unsigned long GetTimecode() const;  // of frame most recently written to file

private:
  StreamVideo* m_pVideo;
  StreamAudio* m_pAudio;  // TODO: accept multiple audio streams

  void Final();

  void WriteEbmlHeader();

  void InitSegment();
  void FinalSegment();

  void InitFirstSeekHead();
  void FinalFirstSeekHead();
  void WriteSeekEntry(unsigned long, long long);

  void InitInfo();
  void FinalInfo();

  void WriteTrack();

  long long m_segment_pos;
  long long m_first_seekhead_pos;
  long long m_info_pos;
  long long m_track_pos;
  long long m_cues_pos;
  long long m_duration_pos;
  const unsigned long m_timecode_scale;  // TODO: video vs. audio
  unsigned long m_max_timecode;  // unscaled

  struct Keyframe
  {
    unsigned long m_timecode;  // unscaled
    unsigned long m_block;  // 1-based number of block within cluster

    Keyframe();   // needed for std::list
    Keyframe(unsigned long timecode, unsigned long block);
  };

  struct Cluster
  {
    // absolute pos within file (NOT offset relative to segment)
    long long m_pos;

    unsigned long m_timecode;

    typedef std::list<Keyframe> keyframes_t;
    keyframes_t m_keyframes;
  };

  typedef std::list<Cluster> clusters_t;
  clusters_t m_clusters;

  void WriteCues();

  void CreateNewCluster(const StreamVideo::VideoFrame*);
  void CreateNewClusterAudioOnly();

  void WriteVideoFrame(Cluster&, unsigned long&);
  void WriteAudioFrame(Cluster&, unsigned long&);

  void WriteCuePoints(const Cluster&);
  void WriteCuePoint(const Cluster&, const Keyframe&);

  // The following flags are use to keep track of whether we've seen
  // EOS already.

  bool m_bEOSVideo;
  bool m_bEOSAudio;
  int m_cEOS;
  int EOS(Stream*);
};

}  // namespace webmmux

#endif  // WEBMMUXCONTEXT_HPP