Unified depth intra coding for 3D video extension of HEVC

With the development of high-efficiency video coding (HEVC), the newest video coding standard, 3D video extension of HEVC (3D-HEVC) has been actively investigated. Since 3D-HEVC uses multi-view texture and depth data for input, various coding tools have been added to HEVC. In 3D-HEVC, on top of the existing 35 HEVC intra modes, eight additional modes exist, which are specifically for depth coding. In this paper, we propose a unified depth intra coding method that incorporates such depth intra modes into the regular intra mode set. In particular, the most rarely used HEVC intra modes are replaced by depth intra modes. As a result, binarization for depth intra modes is removed. Furthermore, the most probable mode selection procedure is modified to consider the elimination of several angular intra modes. The proposed method is implemented and tested on 3D video HEVC test model version 7.0. Simulation results report 2.2 % synthesis gain under all-intra configuration.