Video-server retrieval scheduling and resource reservation for variable bit rate scalable video

State-of-the-art digital video compression produces bursty, variable bit rate video. The bursty nature of compressed video raises challenges in the design of video servers. In this paper, we first present a method for the efficient retrieval of bursty video data from the disk system to the memory of a digital video server. For a single video stream, the proposed retrieval schedule minimizes the buffer requirement for continuous retrieval, given that a fixed disk bandwidth is reserved for the entire duration of retrieval. Secondly, we present an optimal resource-reservation algorithm for multiple video streams based on the proposed retrieval schedule. The resource-reservation algorithm maximizes the number of bursty video streams that ran be supported by a video server given any disk bandwidth and memory resource. Thirdly, we present a progressive display scheme for scalable video that is based on the retrieval schedule and resource-reservation algorithm. Performance evaluations based on simulations using MPEG-2 trace data are presented. For a personal computer with four disks and a memory resource of 120 MB, our approach can support 50%-275% more video streams than previously proposed approaches, depending on the pre-fetch delay that users are willing to tolerate in interactive viewing of videos.