Investigating Shift Equivalence of Convolutional Neural Networks in Industrial Defect Segmentation
This addresses a specific issue in industrial defect segmentation for manufacturing quality control, but it is incremental as it builds on existing robustness methods with novel modules.
The paper tackles the problem of shift equivalence in convolutional neural networks for industrial defect segmentation, where small input shifts cause segmentation fluctuations, and proposes a new down/upsampling layer called CAPS with adaptive windowing and component attention modules, achieving higher equivalence and segmentation performance on multiple datasets compared to state-of-the-art methods.
In industrial defect segmentation tasks, while pixel accuracy and Intersection over Union (IoU) are commonly employed metrics to assess segmentation performance, the output consistency (also referred to equivalence) of the model is often overlooked. Even a small shift in the input image can yield significant fluctuations in the segmentation results. Existing methodologies primarily focus on data augmentation or anti-aliasing to enhance the network's robustness against translational transformations, but their shift equivalence performs poorly on the test set or is susceptible to nonlinear activation functions. Additionally, the variations in boundaries resulting from the translation of input images are consistently disregarded, thus imposing further limitations on the shift equivalence. In response to this particular challenge, a novel pair of down/upsampling layers called component attention polyphase sampling (CAPS) is proposed as a replacement for the conventional sampling layers in CNNs. To mitigate the effect of image boundary variations on the equivalence, an adaptive windowing module is designed in CAPS to adaptively filter out the border pixels of the image. Furthermore, a component attention module is proposed to fuse all downsampled features to improve the segmentation performance. The experimental results on the micro surface defect (MSD) dataset and four real-world industrial defect datasets demonstrate that the proposed method exhibits higher equivalence and segmentation performance compared to other state-of-the-art methods.Our code will be available at https://github.com/xiaozhen228/CAPS.