Error Concealment In Video Communications Using DPCM Bit Stream Embedding
C.B. Adsumilli, S. Mitra · 2006
An error concealment using data hiding (ECDH) technique is proposed to improve the end user perceptual quality of videos that are affected by transmission defects. A 2/spl times/2 set of coefficients from each block of block-based 2D DCT of the video frame is encoded using DPCM and embedded in the frame itself using a low gain spread spectrum watermarking technique. The DPCM bit stream is ordered into a binary block-image, which is approximately 4 times smaller than the video frame, and embedded in the frame's mid-frequencies. At the receiver, the extracted DPCM bits are lexicographically ordered and a reference is reconstructed for error concealing the channel loss affected video frame. The technique is closely compared with a similar approach which embeds halftoned bits of a low resolution version of the video frame in itself. Also, a comparison is done when the DPCM encoded bits are transmitted as side information through the channel rather than as embedded data. Experimental results show that the technique that uses DPCM bit stream embedding is more effective than the other two ECDH techniques as well as most other error concealment algorithms.