aac over rtp live555 打包

void MPEG4GenericRTPSink
::doSpecialFrameHandling(unsigned fragmentationOffset,
unsigned char* frameStart,
unsigned numBytesInFrame,
struct timeval framePresentationTime,
unsigned numRemainingBytes) {
  // Set the "AU Header Section".  This is 4 bytes: 2 bytes for the
  // initial "AU-headers-length" field, and 2 bytes for the first
  // (and only) "AU Header":
  unsigned fullFrameSize
    = fragmentationOffset + numBytesInFrame + numRemainingBytes;
  unsigned char headers[4];
  headers[0] = 0; headers[1] = 16 /* bits */; // AU-headers-length
  headers[2] = fullFrameSize >> 5; headers[3] = (fullFrameSize&0x1F)<<3;


  setSpecialHeaderBytes(headers, sizeof headers);


  if (numRemainingBytes == 0) {
    // This packet contains the last (or only) fragment of the frame.
    // Set the RTP 'M' ('marker') bit:
    setMarkerBit();
  }


  // Important: Also call our base class's doSpecialFrameHandling(),
  // to set the packet's timestamp:
  MultiFramedRTPSink::doSpecialFrameHandling(fragmentationOffset,
    frameStart, numBytesInFrame,
    framePresentationTime,
    numRemainingBytes);
}


参考rfc 3640