David Sarnoff Res. Center, Princeton, NJ.
IEEE Trans Image Process. 1995;4(4):470-7. doi: 10.1109/83.370675.
An algorithm for lost signal restoration in block-based still image and video sequence coding is presented. Problems arising from imperfect transmission of block-coded images result in lost blocks. The resulting image is flawed by the absence of square pixel regions that are notably perceived by human vision, even in real-time video sequences. Error concealment is aimed at masking the effect of missing blocks by use of temporal or spatial interpolation to create a subjectively acceptable approximation to the true error-free image. This paper presents a spatial interpolation algorithm that addresses concealment of lost image blocks using only intra-frame information. It attempts to utilize spatially correlated edge information from a large local neighborhood of surrounding pixels to restore missing blocks. The algorithm is a Gerchberg (1974) type spatial domain/spectral domain constraint-satisfying iterative process, and may be viewed as an alternating projections onto convex sets method.
提出了一种用于基于块的静态图像和视频序列编码中丢失信号恢复的算法。由于块编码图像的传输不完美而导致出现丢失块的问题。由此产生的图像存在没有正方形像素区域的缺陷，这些区域即使在实时视频序列中也会被人类视觉明显感知到。错误隐藏的目的是通过使用时间或空间插值来掩盖丢失块的效果，从而创建一个主观上可接受的真实无错误图像的近似值。本文提出了一种空间插值算法，该算法仅使用帧内信息来隐藏丢失的图像块。它试图利用来自周围像素的大局部邻域的空间相关边缘信息来恢复丢失的块。该算法是一种 Gerchberg（1974）类型的空域/谱域约束满足迭代过程，可视为交替投影到凸集方法。
