A systematic method for illusory contour

The smooth completion of fragmented curve segments even when sufficient contrast is lacking or in the presence of occlusions is an intrinsic skill of human visual system and illusory contour shows one of the compelling examples. This paper focuses on illusory contour extraction. We propose an algorithm to simulate the perceptual completion process of illusory contour. This approach hinges on two basic features: the orientations of edges and the key points. From these two kinds of features a contour organization process is performed and then the contour gaps are completed by Euler spiral curves. Tests have been administered on classical illusory contour figures. These experiments show that our algorithm is superior to previous works with respect to simplicity and can tackle two kinds of contour gaps in a robust way.