摘要： 传统的视频重建方法采用均匀速率进行采样，其重建质量难以提高。针对该问题，提出一种新的变速率稀疏采样方法。使用自适应阈值方法检测帧差图像的边缘，将视频像素块分类为主动块和被动块，对主动块使用高速率采样，而对被动块使用低速率采样，结合平滑滤波和凸集投影的迭代步骤，对视频进行分块优化的重建。该方法与传统的均匀速率采样法的不同之处在于利用了视频的运动纹理特征，对运动的像素块使用高速率采样，以此提高视频的重建质量。仿真结果表明，与传统的均匀速率采样法相比，提出的变速率采样法可减少重建图像的块状效应，峰值信噪比更高。

关键词: 视频重建, 帧差, 边缘检测, 变速率采样, 分块优化, 峰值信噪比

Abstract: The uniform sampling rate is commonly used in the video reconstruction so that it is difficult to improve its reconstruction quality. A novel method for variable rate sparse sampling is proposed in this paper. The edge of frame difference is detected by the adaptive threshold. And the pixel blocks are classified as active blocks and passive blocks according to the edge. The active blocks are sampled by the high rate while the passive blocks are sampled by the low rate. Combining the smooth filtering and the iterative steps for projection of convex sets, video reconstruction is accomplished by the block optimization. Different from the commonly used uniform sampling, the proposed method properly exploits the motion texture of video. The pixel blocks with salient motion are sampled by the high rate so that the reconstruction quality is enhanced. Simulation results show that the proposed variable sampling method can reduce the block artifacts and obtain higher peak signal to noise rate than the uniform sampling method.

Key words: video reconstruction, frame difference, edge detection, variable rate sampling, block optimization, peak signal to noise rate

中图分类号: 

• TP391