MPEGVideoStreamFramer.hh

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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
more details.
 
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// "liveMedia"
// Copyright (c) 1996-2024 Live Networks, Inc.  All rights reserved.
// A filter that breaks up an MPEG video elementary stream into
//   headers and frames
// C++ header
 
#ifndef _MPEG_VIDEO_STREAM_FRAMER_HH
#define _MPEG_VIDEO_STREAM_FRAMER_HH
 
#ifndef _FRAMED_FILTER_HH
#include "FramedFilter.hh"
#endif
 
class TimeCode {
public:
  TimeCode();
  virtual ~TimeCode();
 
  int operator==(TimeCode const& arg2) const;
  unsigned days, hours, minutes, seconds, pictures;
};
 
class MPEGVideoStreamFramer: public FramedFilter {
public:
  Boolean& pictureEndMarker() { return fPictureEndMarker; }
      // a hack for implementing the RTP 'M' bit
 
  void flushInput(); // called if there is a discontinuity (seeking) in the input
 
protected:
  MPEGVideoStreamFramer(UsageEnvironment& env, FramedSource* inputSource);
      // we're an abstract base class
  virtual ~MPEGVideoStreamFramer();
 
  void computePresentationTime(unsigned numAdditionalPictures);
      // sets "fPresentationTime"
  void setTimeCode(unsigned hours, unsigned minutes, unsigned seconds,
                   unsigned pictures, unsigned picturesSinceLastGOP);
 
protected: // redefined virtual functions
  virtual void doGetNextFrame();
  virtual void doStopGettingFrames();
 
private:
  void reset();
 
  static void continueReadProcessing(void* clientData,
                                     unsigned char* ptr, unsigned size,
                                     struct timeval presentationTime);
  void continueReadProcessing();
 
protected:
  double fFrameRate; // Note: For MPEG-4, this is really a 'tick rate'
  unsigned fPictureCount; // hack used to implement doGetNextFrame()
  Boolean fPictureEndMarker;
  struct timeval fPresentationTimeBase;
 
  // parsing state
  class MPEGVideoStreamParser* fParser;
  friend class MPEGVideoStreamParser; // hack
 
private:
  TimeCode fCurGOPTimeCode, fPrevGOPTimeCode;
  unsigned fPicturesAdjustment;
  double fPictureTimeBase;
  unsigned fTcSecsBase;
  Boolean fHaveSeenFirstTimeCode;
};
 
#endif