APPARATUS AND METHOD FOR REDUCING NOISE OF IMAGE BASED ON DISCRETE WAVELET TRANSFORM

摘要

PURPOSE: An apparatus for reducing noise of an image based on discrete wavelet transform is provided to improve the image quality compared with existing noise removal technique. CONSTITUTION: A wavelet transform unit(110) generates a plurality of sub bands by performing discrete wavelet transform with an original image. An alpha map generating unit(120) generates alpha map data coping with each wavelet coefficient. A coefficient correcting unit(130) produces the correction wavelet coefficient value. A coefficient transform unit(140) changes a wavelet coefficient with big entropy value into zero. An inverse transform unit(150) generates a corrected image in which noise is removed by performing reverse discrete wavelet transform.