Fig. 1. (a) Composition diagram and (b) physical diagram of system hardware

Fig. 2. Image obtained online

Fig. 3. Calculation process of correlation

Fig. 4. Flow chart of pyramid acceleration algorithm

Fig. 5. Fast positioning of workpieces

Fig. 6. Diagram of bilinear interpolation

Fig. 7. Cross section of negative LoG operator

Fig. 8. Enhanced surface image of the workpiece

Fig. 9. Defect segmentation image after the threshold processing

Fig. 10. Defect segmentation image for another workpiece

Fig. 11. System software interface

Fig. 12. (a) Location image; (b) regional enhanced image; (c) defect segmentation image