METHOD AND AN APPARATUS FOR FILTERING AN IMAGE BY USING A PSEUDO-RANDOM FILTER, PARTICULARLY FOR REMOVING ARTIFACTS BY USING A PSEUDO-RANDOM FILTER

摘要

PURPOSE: A method and an apparatus for filtering an image by using a pseudo-random filter are provided to efficiently remove artifacts occurring in image encoding and decoding procedures by filtering a block including identical or similar pixel values through a pseudo-random filter.;CONSTITUTION: A similarity determination unit(110) determines the similarity between pixel values of a first block, and a random filtering unit(120) generates a second block by applying a pseudo-random filter to the first block based on the determination result. The similarity determination unit counts the frequency in which the absolute value of difference values between adjacent pixel values in a certain direction is lower than a first threshold value in the first block. If the ratio of the counted frequency is larger than the second threshold value, the random filtering unit uses the pseudo-filtering unit to generate the second block.;COPYRIGHT KIPO 2011