The algorithms such as Hough transform and neural network for recognizing circle and polygons have the disadvantage of costing too much calculation and time.Based on the tunable filter

an algorithm for recognizing geometrical shapes automatically was proposed.After the energy image and directional angle image were gotten by the tunable filter from the original image

the angle and the line number were calculated from the angle and perpendicular histogram to recognize the polygons and circle.The results illuminate that the circle and polygons such as the triangle and the square with noise can be fast detected by this algorithm.