MIP larger than 64x64 CU

[bheng]

The decoder doesn't support MIP CU sizes larger than 64x64. The code changes for JVET-P0803 include checks, such as the following, that error/exit/crash when the decoder sees such cases.

#if JVET_P0803_COMBINED_MIP_CLEANUP
void IntraPrediction::initIntraMip( const PredictionUnit &pu, const CompArea &area )
{

CHECK( area.width > 64

area.height > 64, "Error: block size not supported for MIP" );

...

}

The syntax and draft-text supports MIP up to 128x128 CUs because there are no conditions on the presence of the intra_mip_flag.

It's not clear that this "up to 128x128" change was actually adopted. And the current CHECK in the code above appears to match the JVET-P0803 proposal.

"MIP is allowed up to 64x64 regardless of the maximum transform size, where TU tiling is performed for larger CUs as in JVET-P0352 [5] and JVET-P0198 [8].."

Specifically, the proposal does not say "MIP is allowed up to 128x128 ...". And, as noted above, the associated code for the proposal treats it as an invalid case.

So either, this "up to 128x128" change was adopted and the decoder code, like the check above, should be fixed/removed. Or this wasn't adopted, and the text and syntax should change to include the corresponding conditions on the presence of the intra_mip_flag.

[XiangLi]

Fixed in ​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/merge_requests/1129