A simplified dual-bitstream MPEG video streaming system with VCR functionalities

Nowadays, video playback devices have only limited fast-forward/backward playback and even they cannot provide backward playback. The limitation is due to the motion compensated prediction technique adopted in the MPEG standards. One possible way to support browsing functionalities is to store an additional reverse-encoded bitstream into the server. However, this additional bitstream increases the storage requirement of the video server significantly. In this paper, we exploit the redundancy inherent between the forward and reverse-encoded bitstreams in order to achieve a substantial reduction on the size of the reverse-encoded bitstream. The server accesses and manipulates various macroblocks fiom the forward and reverse-encoded bistreams to facilitate various browsing operations. Experimental results show that, as compared to the conventional dual-bitstream scheme, the new scheme significantly reduces the storage requirement due to the additional reverse-encoded bitstream.