Loss-resilient ATM protocol architecture for MPEG-2 videocommunications

摘要

MPEG-2 video communications over ATM networks is one of the mostnactive research areas in the field of computer communications. In thentransmission process of a variable bit rate video signal over an ATMnnetwork, cells are inevitably exposed to delays, errors, and losses duento the statistical multiplexing used in these networks. These phenomenanaffect the quality of the video signal, and without adequate measures toncontrol the propagation of the impairments, the quality of the servicenmay fall below acceptable levels. In this paper, we study the impact ofncell losses on the quality of an MPEG-2 video sequence encoded in anvariable bit rate mode. We introduce a set of control mechanisms atndifferent levels of the protocol architecture to be used in MPEG-2-basednvideo communications systems using ATM networks as their underlyingntransmission mechanism. Our results (using different video sequences)nshow the effectiveness to improve the video quality by using anstructured set of control mechanisms to overcome for the loss of cellsncarrying VBR MPEG-2 video streams. We argue that in order to be able toncreate video systems able to cope with cell losses encountered inncomputer communications systems, a structured set of error-resilientnprotocol mechanisms is needed