Variable block size-based MCFI with fixed block size motion estimation

Recently, motion-compensated frame interpolation (MCFI) has been paid attention for frame rate up-conversion. However, distortions will occur at block boundaries since motion vectors (MVs) are usually estimated in a block-by-block manner. In this paper, we propose a MCFI method using motion compensation with variable block size. To simplify time-consuming motion estimation, we derive MVs for blocks with various sizes from those obtained by fixed block size motion estimation. Our proposed MCFI improves objective and subjective qualities of interpolated video sequences compared to the fixed block size-based MCFI.