VDR PES-Pakete zu originalen Paketen assemblieren

ePesHeader AnalyzePesHeader(const uchar *Data, int Count, int &PesPayloadOffset, bool *ContinuationHeader)
{
  if (Count < 7)
     return phNeedMoreData; // too short


  if ((Data[6] & 0xC0) == 0x80) { // MPEG 2
     if (Count < 9)
        return phNeedMoreData; // too short


     PesPayloadOffset = 6 + 3 + Data[8];
     if (Count < PesPayloadOffset)
        return phNeedMoreData; // too short


     if (ContinuationHeader)
        *ContinuationHeader = ((Data[6] == 0x80) && !Data[7] && !Data[8]);


     return phMPEG2; // MPEG 2
     }


  // check for MPEG 1 ...
  PesPayloadOffset = 6;


  // skip up to 16 stuffing bytes
  for (int i = 0; i < 16; i++) {
      if (Data[PesPayloadOffset] != 0xFF)
         break;


      if (Count <= ++PesPayloadOffset)
         return phNeedMoreData; // too short
      }


  // skip STD_buffer_scale/size
  if ((Data[PesPayloadOffset] & 0xC0) == 0x40) {
     PesPayloadOffset += 2;


     if (Count <= PesPayloadOffset)
        return phNeedMoreData; // too short
     }


  if (ContinuationHeader)
     *ContinuationHeader = false;


  if ((Data[PesPayloadOffset] & 0xF0) == 0x20) {
     // skip PTS only
     PesPayloadOffset += 5;
     }
  else if ((Data[PesPayloadOffset] & 0xF0) == 0x30) {
     // skip PTS and DTS
     PesPayloadOffset += 10;
     }
  else if (Data[PesPayloadOffset] == 0x0F) {
     // continuation header
     PesPayloadOffset++;


     if (ContinuationHeader)
        *ContinuationHeader = true;
     }
  else
     return phInvalid; // unknown


  if (Count < PesPayloadOffset)
     return phNeedMoreData; // too short


  return phMPEG1; // MPEG 1
}