Analysis of Conditional PDF-Based Split VQ

The split vector quantization (SVQ) method results in a ldquocoding lossrdquo due to the independent quantization of split subvectors. To recover the coding loss, conditional pdf-based split vector quantization methods were proposed recently. For a multivariate Gaussian source, we theoretically derive the expression of rate-distortion (R/D) performance for conditional pdf-based split vector quantization (CSVQ) method, using high rate quantization theory and optimum bit allocation. We also derive the rate-distortion performance expression of traditional SVQ method and, thus, quantify the coding gain of CSVQ method over SVQ method.