<title>Region-based DCT image coding scheme</title>

Abstract

This paper describes an attempt to broaden the scope of conventional block-based DCT image coding, by allowing some variation in quantization of DCT values for different blocks in the image. Blocks belonging to each individual spatial region in the image are afforded a particular level of quantization selected for that region. This approach allows desirable levels of compression efficiency and visual quality to be achieved for different parts of the reconstructed image. The scheme offers improved overall balancing of fidelity performance, as well as benefits for applications which undertake further processing using the image regions, such as video coding.