id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
335	Chroma qp offset syntax element missing	jonathang		"In VTM 5.0 within CABACReader::transform_unit, the function CABACReader::cu_chroma_qp_offset may decode a chroma qp offset from the bitstream:

void CABACReader::cu_chroma_qp_offset( CodingUnit& cu )
{
  RExt__DECODER_DEBUG_BIT_STATISTICS_CREATE_SET_SIZE2( STATS__CABAC_BITS__CHROMA_QP_ADJUSTMENT, cu.blocks[cu.chType].lumaSize(), CHANNEL_TYPE_CHROMA );

  // cu_chroma_qp_offset_flag
  int       length  = cu.cs->pps->getPpsRangeExtension().getChromaQpOffsetListLen();
  unsigned  qpAdj   = m_BinDecoder.decodeBin( Ctx::ChromaQpAdjFlag() );
  if( qpAdj && length > 1 )
  {
    // cu_chroma_qp_offset_idx
    qpAdj += unary_max_symbol( Ctx::ChromaQpAdjIdc(), Ctx::ChromaQpAdjIdc(), length-1 );
  }
  /* NB, symbol = 0 if outer flag is not set,
   *              1 if outer flag is set and there is no inner flag
   *              1+ otherwise */
  cu.chromaQpAdj = cu.cs->chromaQpAdj = qpAdj;
}

This function follows directly after code that may decode the cu_qp_delta_abs and cu_qp_delta_sign_flag syntax elements. In the spec (section 7.3.7.10) there is no corresponding syntax element for chroma qp offset."	defect	closed	minor		spec	VVC D5 v10	fixed		ksuehring bbross XiangLi fbossen jvet@…