利用视频与深度图相关性的深度图帧内编码

Depth map intra coding based on correlation between video and depth maps

因现有帧内编码算法编码深度图中含有边缘的宏块编码效率较低,故提出了一种利用视频与深度图之间相关性的边缘跳过帧内编码方法.该方法利用聚类方法从当前深度编码宏块及其参考像素部分对应的视频区域获得边缘信息,以此作为当前深度编码宏块及其参考像素的分割边缘信息,然后利用所得分割边缘信息将参考像素映射到当前编码宏块作为预测值.为了滤除聚类方法获得的分类信息中存在的噪点或者毛刺对预测的干扰,提出了双向扫描滤波的方法.利用所提边缘跳过帧内预测方法,可以跳过对边缘宏块中复杂边缘的编码,甚至边缘宏块完全被跳过不编码.实验结果表明,与原始编码算法相比,所提方法平均可减少24.25%的码率,峰值信噪比平均提升了0.70dB,主观编码质量也得到明显增强.

Since the coding efficiency of the depth macro-block （MB） that contains the edge by using the existing intra coding method is low, an edge skip intra coding method based on the correlation between video and depth maps is proposed. In this method, the segmentation information of the current depth MB and its reference samples is derived from the corresponding video regions by clustering. With the segmentation information, the reference samples are mapped to the current MB as predicted samples. In order to remove the disturbance to the segmentation information caused by the noise point and burr from the clustering operation, a refinement operation is proposed by bi-direction scanning. With the proposed method, the complex edge of an edge MB, even a total edge MB, is skipped without coding. Experimental results demonstrate that compared with the original coding algorithm, the proposed method can reduce the coding bit-rate by 24.25% and increase the peak signal-to-noise ratio （PSNR） by 0.70 dB on average. Besides, the subjective coding quality is also improved obviously.