High performance deartifacting filters in video compression

Artifacts commonly exist in the coded image and video. Non-local Kuan's (NLK) filter has achieved the state-of-the-art performance on deartifacting the coded image, but there is no literature incorporating it into video scenarios. In the paper, we propose two loop filters, quadtree-based NLK (QNLK) filter and quadtree-based overcomplete NLK (QOCNLK) filter, for video coding. In the proposed techniques, NLK and overcomplete NLK filters are used to restore quantized residual transform coefficients, and quadtree-based signaling strategy is used for adaptive filtering control. Experimental results show that the proposed techniques achieve significant bitrate saving and visual quality improvement, compared with H.264/AVC High Profile.