Entropy coding techniques can be applied to communicate the quantization indices from a source encoder that performs the classification stage to a decoder that performs the reconstruction stage. One way to do this is to associate each quantization index formula_10 with a binary codeword formula_55. An important consideration is the number of bits used for each codeword, denoted here by formula_56. As a result, the design of an formula_39-level quantizer and an associated set of codewords for communicating its index values requires finding the values of formula_42, formula_59 and formula_60 which optimally satisfy a selected set of design constraints such as the "bit rate" formula_61 and "distortion" formula_62.