SYSTEM AND METHOD FOR AUTOMATICALLY DETECTING A MURA DEFECT USING MASK FILTERING IN WAVELET TRANSFORM

摘要

The present invention relates to a system and a method to automatically detect a stain defect by using mask filtering in wavelet conversion. The system includes: an image obtaining part obtaining an original image of an object; an image processing part including a background image generating part, generating a background image by using a discrete cosine transform (DCT) coefficient, and a wavelet conversion part generating a wavelet detail coefficient and a wavelet approximation coefficient by removing the background image component from the original image and applying wavelet conversion; and an image analyzing part including a stain mask generating part, generating a stain mask by using a standard deviation of the wavelet approximation coefficient, and a mask filtering part emphasizing a stain by applying mask filtering to the wavelet detail coefficient. Therefore, the present invention is capable of effectively detecting a stain defect having a small contrast difference with a background area.