Object extraction is an essential branch of the computer vision, concerned with the analysis of images to extract useful information from the world. It covers wide range of image processing fields and plays an important role in computer vision. In this dissertation, contour detection is mainly discussed to realize object extraction, realized in three steps: edge detection, contour segment detec...

Level Set Algorithm (LSA) is one of the efficient tools of edge detection and contour extraction, which has been applied to radar, medical, and other images processing successfully. However, the procedure using LSA will cost a lot of time when applied to high-resolution images. This paper provides two novel approaches that can enhance the detection speed. In the first method, the moving step en...

Due to distortion, noise, segmentation errors, overlap, and occlusion of objects in digital images, it is usually impossible to extract complete object contours or to segment the whole objects. However, in many cases parts of contours can be correctly reconstructed either by performing edge grouping or as parts of boundaries of segmented regions. Therefore, recognition of objects based on their...

In the manufacture of chips, it is important to detect defects assess whether chip potentially damageable that could cause unnecessary cost. Most assessment rules are set in light characteristics determined by defect contours, such as area and range. However, conventional image process methods seldom show a satisfactory performance on chips with complex structures because they difficult disting...