JVET-K0104 CE4-related: History-based Motion Vector Prediction [L. Zhang, K. Zhang, H. Liu, Y. Wang, P. Zhao, D. Hong (Bytedance)]

This contribution presents a History-based Motion Vector Prediction (HMVP) method for inter coding. In HMVP, a table of HMVP candidates is maintained and updated on-the-fly. After decoding a non-affine inter-coded block, the table is updated by adding the associated motion information as a new HMVP candidate to the last entry of the table. A First-In-First-Out (FIFO) or constraint FIFO rule is applied to remove and add entries to the table. The HMVP candidates could be applied to either merge candidate list or AMVP candidate list. It is asserted that the line buffer size is kept unchanged compared to VTM. When the merge candidate list size is extended by 10, compared with VTM-1.0, simulation results reportedly show that HMVP with FIFO and 16 entries of the table achieves 1.00%, 0.51% and 1.04% BD rate reduction for RA Main10, LDB Main10, and LDP Main10 configurations respectively. Compared with BMS-1.0, simulation results reportedly show that HMVP achieves 0.81%, 0.42% and 0.44% BD rate reduction for RA Main10, LDB Main10, and LDP Main10 configurations respectively. In addition, when the merge candidate list size is kept unchanged, compared with VTM-1.0, 0.82% BD rate reduction for RA Main10 configurations are reported by applying HMVP with constraint FIFO and only 8 entries of the table.

Reviewed in Track B (chaired by JRO) Sunday 1330

Very promising (as compared to other merge proposals from CE4), much less complexity

Method is applied both for merge and MV prediction, gain on MV prediction is said to be <0.2%

Only partial results for BMS available so far

Test 3 is most promising in terms of complexity vs. performance

Further study in a CE was requested. Also study the impact on merge and MV prediction separately.

Results for test 3 configuration only for merge were requested for further discussion, RA in BMS should be provided (confirmed by crosscheck). This could be a candidate for BMS adoption, if it provides reasonable gain.