Blowhole Detection Based on Bidirectional Enhancement and Omnidirectional Analysis for X-Ray Inspection of Castings

Figure 3

The defect region segmentation process. It comprises three steps: subtraction, edge detection, and region selection. First, the reference image is subtracted from the low sharpening image. Then, the edge of the remaining part is detected from the subtraction result. Finally, the connected areas in the binary image with the appropriate areas are selected.