CvSeq Operation

The normal way:

  CvSeq *seq = cvCreateSeq( 0, sizeof(CvSeq), elem_size, storage );
  cvSeqPush(seq, &elem);

The faster way:

  CvSeq* seq = NULL;
  CvSeqWriter writer;
  cvStartWriteSeq( 0, sizeof(CvSeq), elem_size, storage, &writer );
  //...
  CV_WRITE_SEQ_ELEM( elem, writer );
  //...
  seq = cvEndWriteSeq( &writer );