关键词: 块匹配, 下采样, 运动估计, 运动补偿, 视频降噪

Abstract: A fast block-matching search algorithm based on down-sampling named Down-sampling Three Step Search (DTSS) was proposed. In video sequence, the down-sampling frames of the current frame and the reference frame would be obtained first by bilinear interpolation sampling. Then, the initial motion estimation would be estimated by using Three Step Search (TSS) in the sampling frames. At last, refined search results would be obtained according to the relation between sampling frames and original frames. Due to low-pass characteristic of bilinear interpolation, DTSS can effectively suppress noise and get accurate search of motion vector. On the other hand, while DTSS bears the advantage of sampling technique, it can make block-matching search algorithm faster. The experimental results show that DTSS algorithm outperforms the present searching methods like TSS and Diamond Search (DS) both in search speed and accuracy. Combining this algorithm with the Multi-Hypothesis Motion Compensated Filter (MHMCF) noise reduction algorithm, the experimental results also indicate that this block based search algorithm suits well in video denoising applications.

Key words: block-matching, down-sampling, motion estimation, motion compensation, video denoising