JVET-N0847 CE7-related: Support of signalling default and user-defined scaling matrices [O. Chubach, C.-Y. Lai, C.-Y. Chen, T.-D. Chuang, C.-W. Hsu, Y.-W. Huang, S.-M. Lei (MediaTek), T. Toma, K. Abe (Panasonic), S.-C. Lim, J. Kang (ETRI)] [late]
This contribution is related to JVET-N0090 and JVET-N0204, containing proposed changes to the default scaling matrices and procedure of defining scaling matrices for rectangular transform blocks (TBs). In this contribution, it is proposed to add support for signalling the default and user-defined scaling matrices on top of VTM4.0. The proposal is conforming to the bigger size range for the blocks (from 4×4 to 64×64 for luma, from 2×2 to 32×32 for chroma), rectangular TBs, dependent quantization, multiple transform selection (MTS), large transform with zeroing-out high frequency coefficients (aligned to the one-step definition procedure of scaling matrices for TBs), intra subblock partitioning (ISP), and intra block copy (IBC, also known as current picture referencing, CPR). The proposed method of signalling scaling matrices has been implemented on top of VTM4.0.
The text was reviewed in Track A Tue 03-26 morning; it is implementing the concept as previously sugessted, i.e. use the 4x4 matrix for block sizes 4x4, 4x2, 2x4, and the 8x8 matrix for all other cases, where decimation is applied for 1|2|4xN and Nx1|2|4, and otherwise the HEVC concept of interpolation per direction.
Decision: Adopt JVET-N0847. Some minor text improvements are left to the discretion of the editor.
CE8 related – Screen content coding tools (46)
Contributions in this category were discussed in BoG JVET-N0780 (chaired by X. Xu) except as otherwise noted.