JVET-AJ0223 Non-EE2: Bilateral Filtering for Intra Prediction [W. Yin, K. Zhang, Y. Wang, Z. Deng, N. Zhang, L. Zhao, M. Salehifar, L. Zhang (Bytedance)]

In this contribution, bilateral filtering for intra prediction is proposed. Intra prediction samples are filtered by bilateral filtering before they are used in the later processes.

On top of ECM-14.0, simulation results of the proposed method are reported as below:

AI: -0.12%, -0.08%, -0.09%, 100.8%, 100.5%.

This proposed method is always applied to all intra predicted blocks (not including IBC and IntraTMP blocks).

Existing bilateral filter in ECM-14 is used.

Several experts commented that the gain looked interesting, and expressed interest in studying in EE.

It was commented that the proposed bilateral filter is sometimes applied before PDPC and sometimes after, depending on intra prediction mode. It was suggested to also study two variants where the proposed bilateral filter is applied always before PDPC and always after PDPC.

It was commented that the proposal also includes an orthogonal aspect on interpolation filter for TIMD mode, which should be studied separately.

It was agreed to investigate this in an EE. Study the following subtests:

• Interpolation filter for TIMD as a separate test
• Bilateral filter always before or after PDPC (pick one)
• The proposed bilateral filtering process
• Combination with JVET-AJ0116/JVET-AJ0217 on TIMD filters