Coding Distortion Elimination of Virtual View Synthesis for 3D Video System: Theoretical Analyses and Implementation
For a three dimensional video (3DV) system, coding distortion of texture videos and depth maps could be propagated to virtual views during the view synthesis procedure. In this paper, the coding distortion is considered in the virtual view synthesis. In order to reduce the coding distortion as well as improve the qualities of synthesized virtual views, Wiener filter is utilized in 3DV systems. To ensure that Wiener filter could be implemented on virtual views, the principles of virtual view synthesis and Wiener filter are presented and analyzed in detail. Subsequently, the implementation of Wiener filter is designed for 3DV system. In the proposed method, Wiener filter coefficients of each frame are calculated in the 3DV server, and then transmitted to the 3DV terminal. By employing those Wiener filter coefficients, post filtering on the virtual views could be implemented after the virtual view synthesis procedure. Experimental results demonstrate that a maximum 0.742 dB PSNR gain could be achieved when comparing the proposed method (taking the coding bits of depth maps, texture videos, and that of Wiener filter coefficients into consideration) with the virtual view synthesis method without Wiener filter at the same coding bit rate of a 3DV system.