面向三维高效视频编码的深度图错误隐藏

基于多视点视频序列视点内、视点间存在的相关性，并结合视点间运动矢量共享技术，该文提出一种面向3维高效视频编码中深度序列传输丢包的错误隐藏算法。首先，根据3D高效视频编码(3D-HEVC)的分层B帧预测(HBP)结构和深度图纹理特征，将深度图丢失块分成运动块和静止块；然后，对于受损运动块，使用结合纹理结构的外边界匹配准则来选择相对最优的运动/视差矢量进行基于位移矢量补偿的错误掩盖，而对受损静止块采用参考帧直接拷贝进行快速错误隐藏；最后，使用参考帧拆分重组来获取新的运动/视差补偿块对修复质量较差的重建块进行质量提升。实验结果表明:相较于近年提出的对比算法，该文算法隐藏后的深度帧平均峰值信噪比(PSNR)能提升0.25～2.03 dB，结构相似度测量值(SSIM)能提升0.001～0.006，且修复区域的主观视觉质量与原始深度图更接近。

Depth Map Error Concealment for 3D High Efficiency Video Coding

By using the intra-view and inter-view correlations and the motion vector-sharing, a depth map error concealment approach is proposed for 3D video coding based on the High Efficiency Video Coding (3D-HEVC) to combat the packet loss of the depth video transmission. Based on the Hierarchical B-frame Prediction (HBP) structure in 3D-HEVC and textured features of the depth map, all the lost coding units are firstly categorized into two classes, i.e., motion blocks and static blocks. Then, according to the outer boundary matching criterion combining the texture structure, the optimal motion/disparity vector is chosen for the damaged motion blocks to conduct the motion/disparity compensation based error concealment. Whereas, the direct copy is applied to concealling the damaged static blocks quickly. Finally, for the concealed blocks whose qualities are not ideal, the new motion/disparity compensation blocks reconstructed by the reference frames recombination are applied to improning the qualities of those blocks. The experimental results show that the repaired depth map concealed by the proposed approach can achieve 0.25～2.03 dB gain in term of the Peak-Signal-to-Noise Ratio (PSNR) and 0.001～0.006 gain in term of Structural Similarity Index Measure(SSIM). Moreover, the subjective visual quality of the repaired area is better in lines with the original depth maps.