Patent ID: 7792376

Claim:
A compression encoder for compression and coding of an image signal, comprising: a wavelet transformer that recursively divides an image signal into high- and low-pass components by wavelet transform and generates and outputs transform coefficients in a plurality of bandpass components; an image-quality controller that determines a quantization step size by dividing a quantization parameter which indicates target image quality by a norm of a synthesis filter coefficient; a region-of-interest setting unit that sets at least one region of interest in said image signal; a quantizer that quantizes and sorts said transform coefficients with said quantization step size as well as sorts and bit shifts said transform coefficients on the basis of information on setting said at least one region of interest; an entropy coder that entropy codes said transform coefficients inputted from said quantizer; and a rate controller that controls a rate by truncating part of coded data outputted from said entropy coder so that a total capacity of said coded data meets a target rate.