On Coding and Codebooks in Multimedia Information Systems

Abstract

Multimedia tools are becoming an essential means in human interaction, electronic commerce and markets such as the worldwide web system. This increasing amount of information transmitted via communication channels has to be handled in an efficient manner to avoid congestion and delays in the network service. In this work, a new approach to multimedia data transmission and storage is proposed. One of its basic assumptions is that in many situations the multimedia information could be decomposed into basic components or codewords that represent a significant part of the data. To illustrate the capabilities of the proposed approach, a compression system for video streams is developed and tested. The system is based on the observations that in most multimedia systems, building blocks of recent history of the stream can describe present details of the multimedia information. A straightforward example is taking the background image of a video sequence as a codeword. However, there are more complex codewords such as typical repeated movements in the transmitted image e.g., lip and eye movements of humans in a scene. Experimental results indicate a high compression ratio of more than 100:1, obtaining almost lossless visual reproduction with signal-to-noise ratio higher than 1000:1 (30 db). Unlike MPEG or the like, the proposed approach can be similarly used also for other components in the multimedia stream. Our conclusion is that codewords and codebooks could be very efficient in developing multimedia information systems and transmission methods.