Fast H.264/AVC to HEVC transcoding based on residual homogeneity

The latest High Efficiency Video Coding (HEVC) has achieved better compression performance than H.264/AVC. In order to make full use of the contents encoded by H.264/AVC, high efficient transcoding from H.264/AVC to HEVC is in great need. In this paper, a fast transcoding structure is proposed. It mainly focuses on coding unit (CU) and prediction unit (PU) decision by using blocks´ homogeneity characteristic. The residual homogeneity indicator (RHI) and sum of absolute residual (SAR) value are extracted to early terminate CU partition. Further, the unnecessary PU partitions are excluded by exploring RHI information from H.264/AVC bitstream. Experimental results illustrate that the proposed algorithm achieves about 56.68% complexity saving in terms of encoding time with only 2.2% BDBR loss when compared to the trivial transcoder.