Fast depth intra mode decision using intra prediction cost and probability in 3D-HEVC

3D-HEVC, which is a HEVC-compatible 3D video coding standard, was mainly developed to efficiently compress both a texture image and a depth map. Since the characteristics of the depth map are drastically different from those of the texture image, many advanced tools were adopted for depth intra coding in 3D-HEVC. In particular, a depth modelling mode (DMM) is evaluated to accurately predict sharp edges between objects. As a result, encoding complexity becomes very high. In order to reduce the high complexity, a fast depth intra mode decision method employing intra prediction cost and probability is proposed in this paper. Based on the cost and probability, the proposed method adaptively skips HEVC prediction modes and DMM in the mode decision. Experimental results demonstrate that it significantly reduces the encoding complexity, compared to conventional methods.