CTU splitting algorithm for H.264/AVC and HEVC simultaneous encoding

Abstract

High-Efficiency Video Coding (HEVC) was conceived by the Joint Collaborative Team on Video Coding as the natural successor of the H.264/AVC standard, which has been the most extended digital video standard in all segments of the domestic and professional markets for over 10 years. HEVC roughly doubles the compression A. J. Diaz-Honrubia et al.performance of H.264/AVC in Rate-Distortion terms at the expense of a high computational cost. Thus, most of the previous-generation devices can decode H.264/AVC streams but they cannot decode HEVC yet, while emerging devices are supposed to be able to decode both standards. Video providers should take advantage of bandwidth reduction using HEVC when possible, but they should also provide compatible streams to older devices, making it necessary to encode the same stream using both H.264/AVC and HEVC standards. This paper presents a coding tree unit splitting algorithm for a heterogeneous simultaneous encoding scenario which makes use of information from H.264/AVC encoder to make faster decisions in HEVC. Experimental results show that the proposed algorithm can achieve a good trade-off between coding efficiency and complexity.