C. Sun, “Fast Recovery of Rotational Symmetry Parameters Using Gradient Orientation”, SPIE Journal of Optical Engineering, vol.36, no.4, pp.1073-1077, April 1997.
Symmetry detection is important in the area of computer vision. A simple and fast algorithm for recovery of rotational symmetry parameters has been developed in this paper. The fold number of a rotationally symmetric shape is obtained from the gradient orientation histogram of the input gray level image using Fourier method, based on the relationship between the periodicity of the orientation histogram and the fold number of the symmetric shape. It only takes 0.06 secs CPU time for a 256×256 gray image on a Sun Sparc10. Both simulated and real images have been tested and the results are very convincing.
Rotational symmetry; Orientation histogram; Fold number; Gradient orientation; Fourier transform