Singular point extraction in fingerprints

Hello
Am a final year engg student working on a fingerprint classification project.
I need help with detecting the singular points in a fingerprint image.
Any help provided would be highly appreciated.
Thank you for your help.

I guess you mean whorls and ridges?

You could compare the slopes of lines (following a line pixel by pixel). Where slope changes, that must be a singular point.

However following a line may not always be possible, since you cannot be sure of the quality of the image, and you cannot be sure there won't be gaps in lines.

So I think it is easier to search for parallel lines, which are not the singular points in a fingerprint. Find the areas where parallel lines can be mapped out easily. The places that cannot be mapped out are singular points.