ADAPTIVE BLOCK-TYPE NOISE ELIMINATION METHOD FOR STILL IMAGE/DYNAMIC IMAGE USING TEXT/EDGE DETECTION TECHNOLOGY

摘要

PROBLEM TO BE SOLVED: To eliminate the block-type noise artifacts of a reconstituted image especially when the compression ratio is high in the compression of a digital image and a video. SOLUTION: This edge/text detection technology can identify text regions and the filtering is completely avoided in these regions. This technology can distinguish flat regions from the text regions. The filtering applied to the flat regions is, therefore, selected to be stronger than the filtering applied to the text existing regions. Since whether the filtering is to be applied or not is decided according to the contents of an image instead of a bit rate, the edge/text detection technology can be applied to the images with different compression ratios.