Error-resilient video coding using long-term memory prediction and feedback channel

The MC-DCT-based video coding has been generally used for its efficiency and easy implementation, but it is very vulnerable in error-prone environments. In this paper, we address an error-resilient video coding using multiple reference frame, based on the long-term memory motion compensated prediction (LTMP) (IEEE Trans. Circuits Syst. Video Technol. 9 (1) (1999) 70), and an error concealment technique associated with the proposed technique. The rate-distortion optimization of T. Wiegand et al. (1999) is modified by adding dispersion measure of the temporal motion vectors in order to provide the error-resiliency and much improved error concealment performance. Also, the proposed algorithm confines the temporal error propagation using negative acknowledgement in feedback channel, in which both the corrupted area by channel errors and the error-propagated area are estimated and removed from the search region for the motion compensation. Thus, the proposed algorithm yields the similar performance to the forced intra update (FIU) in terms of the PSNR, but avoids the abrupt increase in the bitrate, resulting in more efficient network utilization than the FIU. By the computer simulations, we shall demonstrate that the proposed technique provides an acceptable performance both subjectively and objectively in error-prone environments, as compared with H.263 and LTMP, with or without the feedback messages.