Using revision r858 In TEncAdaptiveLoopFilter.cpp: 5270, the variable iSignDown2:

        iSignDown2 = xSign(pRec[iStride] - pRec[0]);

should be as follows

        iSignDown2 = xSign(pRec[iStride+1] - pRec[0]);

This bug is related to SAO_EO_2 (one type of SAO) in the LCU boundary. This modification make the meaning of SAO_EO_2 in the LCU boundary consistent with the rest of the LCU region. The BD-rate will improve about 0.01%.

Using revision r804

In TEncGop.cpp:385, setting of non-cross-ALF is guarded by ALF being in use:

      if(pcSlice->getSPS()->getUseALF())
      {
       ...
      }

Later, however, at around line 509:

#if MTK_SAO
          if ( pcSlice->getSPS()->getUseALF() || (pcSlice->getSPS()->getUseSAO()) )
...
            m_pcAdaptiveLoopFilter->startALFEnc(pcPic, m_pcEntropyCoder );

The ALF process is called without the correct state being set.

--MRG=0 causes the encoder to fail in HE configs. Since the HM introduces a flag into the SPS which is not present in the WD, it's probably best to remove this option and the SPS coding. A patch to do this is attached.