Surface defect detection algorithm for printing roller based on global contrast and edge gradient

In view of the complex surface condition of printing roller, a defect salience algorithm based on global contrast and edge gradient is proposed. This algorithm uses gamma transform to adjust the overall brightness of the image, and then obtains a salience map by LC algorithm; at the same time, Canny edge detection is performed on the initial image, and then morphological operation is performed to obtain another salience map. Finally, image fusion algorithm is used to fuse the images obtained by the two algorithms to get the final defect salience map and complete the salience detection.The experimental results show that the algorithm has high recognition rate and accuracy, which can meet the needs of surface defect detection of printing roller.