METHOD FOR EDGE DETECTION OF IMAGE SIGNAL USING WAVELET COEFFICIENT

摘要

The present invention relates to a method for detecting the directionality of the edge of the image, and more particularly to a method for detecting the directionality of the edge from the coefficient of the compressed region of the image data. An edge direction detection method of an image using wavelet coefficients according to the present invention includes a first step of extracting an HL band wavelet coefficient and an LH band wavelet coefficient corresponding to a predetermined region of an image; Obtaining a ratio of HL band wavelet coefficients to the extracted LH band wavelet coefficients; And determining a direction of an edge in a predetermined area of the image based on the ratio of wavelet coefficients. According to the present invention, it is possible to omit the decoding process and determine the direction of the edge in the compressed data region, so that image data having a specific edge direction feature can be searched more quickly.;Video data, edge direction, MPEG-7, wavelet transform