Internal Contour Extraction Algorithm Based on Quadratic B-spline for Images of Hot Long Shaft Forgings

Abstract

It is necessary that the internal and external contours are extracted from the image of hot long shaft forgings, while the forgings are measured by CCD measurement method. In the light of the blurry internal edges in the image of the hot forging, a method based on quadratic B-spline curve is employed to extract feature points. In order to remove the pseudo features, a method based on maximum correlation is presented. In accordance with continuity of the internal contours, quadratic B-spline curve is used to fit the internal contours. Experiments show that this algorithm can effectively extract accurate internal contours for images of hot squaring and chamfering forgings. The extracted contours could provide basic data for subsequent 3D reconstruction and geometric measurements.