International organisation for standardisation organisation internationale de normalisation

5.17.2.4Intra prediction filtering

5.17.2.4.1.1.1.1.1JCTVC-H0120 Non-CE6: Improvement of Intra DC prediction for cases without neighbouring samples [A. Duenas, F. Javier Roncero (Cavium)]

This contribution proposed an intra prediction process for the cases where no neighbouring samples are available. This contribution includes adding new elements to the syntax and a decoding process that will support this new intra prediction method.

The contribution proposes to add an intra_DC_X_value parameter to the syntax (where X = luminance, Cb and Cr) that could be used on the cases where the current 128-value prediction is currently utilized to perform intra prediction. Tests considered non-common test condition cases: Low delay P with intra refresh, all intra with slices. Gain was reported as 0.6% for the first, 0.1% for the second case.

There was no support for this among the experts.

5.17.2.4.1.1.1.1.2JCTVC-H0238 Non-CE6: Simplification of intra vertical/horizontal prediction [J. Lee, S.-C. Lim, H. Y. Kim, J. S. Choi (ETRI)]

This contribution presentsed a simplification of intra vertical and horizontal prediction by removing a division operation in the secondary boundary filtering process. The proposed method replaces the division operation by right shift operation in the HM, and removes a comparer in the WD. It was reported that the average BD bit rate is zero in Intra, both for High-Efficiency (HE) and Low-Complexity (LC) configurations.

Two experts (including the cross-checker) expressed support. It seemed to be an obvious cleanup. Decision: Adopted.

5.17.2.4.1.1.1.1.3JCTVC-H0614 Crosscheck of ETRI proposal (JCTVC-H0238) on simplification of intra vertical/horizontal prediction [K. Sugimoto, A. Minezawa, S. Sekiguchi (Mitsubishi)] [late]

5.17.2.4.1.1.1.1.4JCTVC-H0465 Simplification of mode dependent intra smoothing [G. Li, Nam Ling, Li Song (SCU), L. Liu, Nam Ling, Jianhua Zheng, P. Zhang (HiSilicon)]

A method of mode dependent intra smoothing (MDIS) was proposed. The proposal for MDIS removes intra smoothing filtering for prediction units of size 8x8 pixels. It was reported that disabling intra smoothing on 8x8 prediction units except planar mode has 0.03% and 0.05% coding loss for HE and LC cases, respectively; disabling intra smoothing for all intra modes on 8x8 prediction units reportedly has 0.04% and 0.07% coding loss for HE and LC cases.

There was no support for this among the experts.

5.17.2.4.1.1.1.1.5JCTVC-H0374 Cross-check of Hisilicon JCTVC-H0465 Simplification of mode dependent intra smoothing [X. Wen, O. Au (HKUST)] [late]