Of itu-t sg16 wp3 and iso/iec jtc1/SC29/WG11

JCTVC-M0390 Non-SCE4: Crosscheck of JCTVC-M0114 on inter-layer SAO in SHVC [T.-D. Chuang, Y.-W. Huang (MediaTek)] [late]
JCTVC-M0215 Non-SCE4: Adaptive up-sampling of base layer picture using Simplified Separable bilateral filters [J. Zhao, K. Misra, A. Segall (Sharp)]

This document proposes the use of non-linear and content adaptive “bilateral” filters for inter-layer prediction. In previous proposals, the use of a bilateral filter has shown improvements in coding efficiency – especially as the sampling ratio between layers increases. Here, a lower complexity alternative is proposed that integrates a separable bilateral filter directly into the upsampling process. As a result, the upsampling and filtering operation can reportedly be performed at the same time and without additional buffering. There is reportedly no increase in memory bandwidth or on-chip memory, as opposed to sequentially applying the upsampling and filtering stages. The complexity of the method is asserted to be low – with a worst case of an additional 9 multiplications and 15 additions per sample. Results are reported following SCE 4 test conditions and reportedly show EL+BL rate improvements compared to SHM 1.0 anchors of: −0.9% (AI 2x), −0.2% (AI 1.5x), −0.8% (RA 2x), 0.0% (RA 1.5x), −1.0% (LD-P 2x), −0.3 (LD-P 1.5x). The proposed bilateral filtering is not applied to SNR scalability.

The proposal is not applied to the SNR scalability case.

The proposal includes a 256-entry LUT for reciprocal calculation and another 9-entry LUT for weight calculation.

The gain for the 2x SS approach was particularly emphasized by the contributor. There is little gain in other cases.

CU-level (or higher level) on/off is the only encoder control.

Does not apply to the RefIdx approach.

LD-B was not tested.

Currently, upsampling is in the test model but not the working draft.

Text was not provided in the contribution.

May be desirable to "beef up" the TextureRL approach as a competitor to the RefIdx approach.

The proponent indicated a willingness to provide CU-based upsampling for the SHM software – which was welcomed by the group.

Further study in CE (for checking of complexity analysis, testing of LD-B, trade-off comparison with other proposed features).
JCTVC-M0250 Cross-check results of Non-SCE4: Adaptive up-sampling of base layer picture using Simplified Separable bilateral filters (JCTVC-M0215) [Z. Ma, F. Fernandes (Samsung Electronics)] [late]