Efficient Pu Mode Decision and Motion Estimation for H.264/avc to Hevc Transcoder

H.264/AVC has been widely applied to various applications. However, a new video compression standard, High Efficient Video Coding (HEVC), had been finalized in 2013. In this work, a fast transcoder from H.264/AVC to HEVC is proposed. The proposed algorithm includes the fast prediction unit (PU) decision and the fast motion estimation. With the strong relation between H.264/AVC and HEVC, the modes, residuals, and variance of motion vectors (MVs) extracted from H.264/AVC can be reused to predict the current encoding PU of HEVC. Furthermore, the MVs from H.264/AVC are used to decide the search range of PU during motion estimation. Simulation results show that the proposed algorithm can save up to 53% of the encoding time and maintains the rate-distortion (R-D) performance for HEVC.