M0147 - Mismatch of an adopted element(25 points) in VTM

[JeevaRaj]

As per the meeting notes following elements of DMVR is adopted

• Early termination w/ (0,0) position SAD between list0 and list1
• Block sizes for DMVR W*H>=64 && H>=8
• Split the CU into multiple of 16x16 sub-blocks for DMVR of CU size > 16*16
• Reference block size (W+7)*(H+7) (for luma)
• 25 points SAD-based integer-pel search (i.e. (+-) 2 refinement search range, single stage)
• Bilinear-interpolation based DMVR
• MVD mirroring between list0 and list1 to allow bilateral matching
• “Parametric error surface equation” based sub-pel refinement
• Luma/chroma MC w/ reference block padding (if needed)
• Refined MVs used for MC and TMVPs only

In current VTM version, Adaptive Search pattern is used instead of 25 points raster scan order based exhaustive search for +/- 2 refinement.

[JeevaRaj]

fix is provided in the following merge request
​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/merge_requests/348