A Lagrangian formulation of fixed-rate and entropy / memory constrained quantization 1

A Lagrangian formulation of fixed-rate vector quantization is presented. The formulation provides an alternative version of the classic high-rate quantization approximations for fixed-rate codes of Zador, Bucklew, and Wise which parallels the Lagrangian results for variable-rate codes and it leads to a variation of the classic Lloyd algorithm for quantizer design. The approach also leads to a natural Lagrangian formulation combining both common rate constraints of alphabet size and entropy, effectively providing a Lagrangian formulation of memory and entropy constrained vector quantization.