JVET-N0806 Suggested luma mapping with chroma scaling modifications in JVET-N0220/N0389/N0477 [E. François (Technicolor), Y. Ye (Alibaba), P. Yin (Dolby)] [late]

This contribution uses JVET-N0220 as the base package and combines the following chroma residual scaling related aspects from JVET-N0389 and JVET-N0477:

• From JVET-N0389: when dual tree partitioning is on, the scaling factor is derived using the top-left reconstruction sample neighbouring the luma block containing the luma sample collocated with the top-left sample of the chroma block;
• From JVET-0477: 1) when single tree partitioning is on, and when the block is intra coded, the scaling factor is derived using the top-left reference sample used in intra prediction; 2) chroma scaling factor derivation is conditioned upon chroma cbf’s.

Further, it is proposed to disable chroma residual scaling if the chroma block contains less than or equal to 8 samples.

For SDR content, reported {Y, U, V} BD-rate variations are {0.03%, -0.61%, -0.56%} in RA. For HDR content, reported BD-rate variations are {0.40%, -6.81%, -6.71%} in RA, in terms of wPSNR.

This included a combination of the three docs – the aspects should be studied separately.

Other coding tools (2)

Contributions in this category were discussed Saturday 23 March 1500–1530 (Track A chaired by JRO).