Asymptotic closed-loop design of predictive multi-stage vector quantizers
This work considers the design of a multi-stage vector quantizer (MSVQ) for application to the motion compensated prediction error of video signals. It is well known that the design of predictive vector quantizers suffers from fundamental difficulties due to the prediction loop, which have an impact on the convergence and the stability of the design procedure. We propose an approach to predictive MSVQ design that enjoys the stability of open-loop design while ensuring ultimate optimization of the closed-loop system. The proposed design method is tested on video compression at low bit rates, where it significantly outperforms widely-used closed-loop design techniques, and achieves improvement over the H.263 standard.