Features detection is an important problem in image processing and pattern recognition

the detection result affects the pattern recognition and classification directly. Based on the idea of multi-scale geometric analysis

this paper introduces a new method to detect circles in digital images. Firstly

circles in images are transformed into circles feature domain. Then wavelet analysis is applied in the domain to detect point singularity. The coordinate of singular point is the coordinate of circle to be detected. Gray threshold or grads will be applied when Hough transform is used for gray image to detect circle. This disadvantage is overcome by the new method

and it is directly used for gray image or binary image to detect multi-circle. Finally

the difference between the new method and Hough transform is analyzed and compared.