Extended Intra Block Copy with Adaptive Filtering and Overlapped Block Averaging
Haruhisa Kato, Yoshitaka Kidani, Kei Kawamura, Sei Naito · 2023
Next-generation video coding standards are attempting to improve coding performance compared to conventional standards such as VVC by extending technologies such as intra-block copy (IBC). While IBC in VVC has proven effective for screen content, its adaptation to camera-captured content presents challenges regarding sample fluctuations and the continuity of block boundaries. This paper proposes a novel approach to improve IBC performance for camera-captured content by combining adaptive filtering (F-IBC) and overlapped block averaging (OB-IBC). The F-IBC filters IBC prediction samples using filter coefficients derived from adjacent samples to predict sample fluctuations accurately. The OB-IBC is a weighted average of IBC prediction samples of the current block with adjacent samples of the adjacent block’s reference to connect block boundaries smoothly. Following common test conditions in the joint video experts team, experimental results show improved coding performance with a bitrate saving of 0.1 % over the reference software (ECM 7.0) which investigates the enhanced compression beyond VVC capability.