Statistical characteristics and multiplexing of MPEG streams

This paper presents a study of the statistical characteristics and multiplexing of variable-bit-rate (VBR) MPEG-coded video streams. Our results are based on 23 minutes of video obtained from the entertainment movie, The Wizard of Oz. The experimental setup which was used to capture, digitize, and compress the video stream is described. Although the study is conducted at the frame level (as opposed to the slice level), it is observed that the inter-frame correlation structure for the frame-size sequence involves complicated forms of pseudo-periodicity that are mainly affected by the compression pattern of the sequence. A simple model for an MPEG traffic source is developed in which frames are generated according to the compression pattern of the original captured video stream. The number of cells per frame is fitted by a lognormal distribution. Simulations are used to study the performance of an ATM multiplexer for MPEG streams.