JVET-P0091: Reduction of BDOF mvRefineThres to +/- 15

[bheng]

JVET-P0091 code changes have reduced the BDOF mvRefineThres to +/- 15, here:

#if JVET_P0091_REMOVE_BDOF_OFFSET_SHIFT

const int limit = ( 1 << 4 ) - 1;

#else

const int limit = ( 1 << 5 ) - 1;

#endif

The draft text still uses +/- 31:

"The variable mvRefineThres is set equal to 1 << 5."

It's not clear if that was intentional, or maybe an unintentional interaction with other changes to the code in the same place (P0653 / P0491).

If it was intentional, the text should be updated to match. If it was not intentional, this change in the software should be removed.

[hanhuang]

The modification is intentional. " P0091: BDOF and PROF unification by moving 1-bit right-shift of calculating the BDOF sample offset to the derivation of motion refinement". So the range of motion refinement in BDOF need to be adjusted.

[ksuehring]

Changing the component to spec.

[bbross]

Thanks for bringing that up.
Hence, I will fix it by changing:
"The variable mvRefineThres is set equal to 1 << 5."
to
"The variable mvRefineThres is set equal to 1 << 4."

[bbross]

Fixed it as stated above for JVET-P2001-vC.