Mixing and playback of JPEG compressed packet videos

Abstract

This paper addresses the issue of video mixing, which is to simultaneously display multiple motion videos received from multiple independent sources across a packet switched network. A straightforward approach, which performs mixing at pixel domain, is first analyzed and considered undesirable because of the requirements of large amount of expensive memory and decompression capacity. A new technique, which performs mixing directly with JPEG compressed data, is then introduced. An efficient structure based on this new technique is presented which needs only a frame worth of buffering and decompression regardless of the number of video windows and their sizes. The paper also addresses the packet video playback issue, and proposes two simple heuristics.