SDDA: a method of surface defect data augmentation of hot-rolled strip steel

The detection of surface defects in hot-rolled strip steel is an important step in the production process of hot-rolled strip steel, and it is closely related to the final quality. At present, many researchers have conducted many in-depth studies on the classification of strip steel surface defects and achieved fruitful results. However, current research has always focused on modifying the model; this approach has limited improvement in classification accuracy and often brings a reduction in model efficiency. A data augmentation method named SDDA, which can perform multiscale transformations on the images input to the deep learning models, is proposed and validated on X-SDD dataset by MixNet model. The test results show that after the SDDA data augmentation, the accuracy of the model reached 96.81%, which is 1.71% higher than the previous best result; meanwhile, since the improvement occurs on the data side, it only leads to an increase in training time and does not increase the inference time of the model. Through comparison experiments, it can be found that our data augmentation approach provides significant improvements in multiple metrics such as accuracy and F1 for a variety of deep learning models.