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 can 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 PC with four disks and a memory resource of 120 MBytes, 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.