Aiming at automatically detecting the slight scratch of smooth surface of mobile phone screen

a method for small target segmentation and insignificant defects detection based on “Classification net + Attention U-Net” is presented. The necessary components of smooth surface defect detection system based on the classic U-Net are proposed

including preparation of data set

semantic segmentation network

definition of evaluation standards and loss function

appropriate regularization methods and special initialization method. The reason for failing to detect and false detection of insignificant defects by the constructed classic U-Net are analyzed. An improved scheme of adding segmentation network to classification network and adding the Attention mechanism to the classic U-Net is presented. A network consists of “Classification network + Attention U-Net” is constructed to improve the effects of small target segmentation and insignificant defects detection. The results show that the pixel accuracy rate of defects detection of mobile phone screen arrives 0.997 by the presented improved net. The presented method can meet the actual requirements on detecting the slight scratch defects of the mobile phone screen. It can also provide valuable reference for similar scratch and crack detection of smooth surface of ceramic tiles.