A Data-Driven Probabilistic CTU Splitting Algorithm for Fast H.264/HEVC Video Transcoding

High Efficiency Video Coding was developed by the JCT-VC to replace the current H.264/AVC standard, which has dominated digital video services in all segments of the domestic and professional markets for over ten years. Therefore, there is a lot of legacy content encoded with H.264/AVC, and an efficient video transcoding from H.264 to HEVC will be needed to enable gradual migration to HEVC. HEVC adopts a quad tree-based Coding Unit block partitioning structure that is flexible in adapting various texture characteristics at the expense of a high computational cost. This paper presents a data-driven probabilistic CTU splitting algorithm that is designed to exploit the information gathered at the H.264/AVC decoder in order to make faster decisions on CU splitting in HEVC. Experimental results show that the proposed algorithm can achieve a good tradeoff between coding efficiency and complexity compared with the anchor transcoder, and, moreover, it outperforms other related works available in the literature.