Adaptive vector quantization of video for packet switched networks

The authors describe a novel adaptive vector quantization (VQ) scheme suitable for packet video. The technique is shown to provide flexibility in selecting the desired image quality, without the need to send the code vectors themselves. A large codebook is divided into two parts, called higher and lower priority sections, representing common and specific characteristics of images. Entries in the two sections are reorganized and/or exchanged as a function of the usage of the code vectors therein. The rate and extent of adaptation are dictated by the update interval and the desired level of quality, respectively, without requiring any transmission of the vectors themselves. Experimental results are presented