Fast Depth Intra Mode Decision Based on DCT in 3D-HEVC

The state-of-the-art 3D High Efficiency Video Coding (3D-HEVC) is an extension of the High Efficiency Video Coding (HEVC) standard dealing with the multi-view texture videos plus depth map format. But current 3D-HEVC with all intra mode prediction leads to extremely high computational complexity. In this paper, we propose two techniques to speed up the encoding of depth video, including DCT decision and fast CU split decision. For DCT decision, early determination of Depth Modeling Modes (DMMs) is performed if the DCT coefficients in the lower right part of the current Coding Unit (CU) are completely zero. For fast CU split decision, current CU is split when the variance of CU is bigger than threshold. Experimental results demonstrate that the proposed decision can reduce 52.45% coding runtime on average while maintaining considerable rate-distortion (RD) performance as the original 3D-HEVC encoder.