MPEG-2视频码流中直流系数的错误检测和隐藏技术

Error Detection and Concealment Technique of DC for MPEG - 2 Video Bitstream

本文以离散余弦变换(DCT Discrete Cosine Transform)为基础,对采用DCT编码的MPEG-2视频码流中的频域直流系数(DC Direct Coefficient)错误进行了详尽的分析,并对其导致的视频图像的错误结果做了说明。根据图像光滑性原理,提出了DC错误的检测方法。由于其错误通常不会改变图像的细节,因此对此类错误的隐藏,本文提出了一种新的隐错算法,取代了常用的替代法和内插法。仿真实验的结果表明其效果是十分有效的,且明显优于内插算法。

This paper presents a novel error concealment technique based on DC (Direct Coefficient) values in DCT (Discrete Cosine Transform) instead of replacing method and interpolation method. Assuming a smoothness constraint on image intensity , the detection method of errors is proposed, and the image quality influenced by the error of the DC values is analyzed in detail. Analyzed result shows that the error of the DC values doesn' t usually have effect on the image detail and only make image become bright or dark. Computer simulation results show that our approach is efficient and more excellent than spatial interpolation method.