Application-driven computation of optimum quantization tables for DCT-based block coders

In this paper we propose a method for computing optimal quantization tables for specific images. The main criterion for this processing is the allocation of bandwidth in frequency subspaces in the DCT-domain according to power metrics obtained from the transform coefficients. Choice of the weights determines the subjective importance of each frequency coefficient as well as its contribution the finally perceived image. The simultaneous requirement that the quantization tables yield data compression comparable to the one achieved by the baseline JPEG scheme at various quality factors (QF) imposes an additional constraint to the proposed model.