How to Locate Alignment Marks in an Image

Question

I am designing a system that will scan in standardized forms to images (e.g., TBitmap). I would like to identify alignment marks on these pages and use the locations of the

Answer 1

For mark above you can use Hough transform for circles and lines, then check if any cross-line is in the center of any circle then it is your mark. I am not sure about delphi but Hough transform algorithm is well known and implemented in a plenty of libs.