Shallow arc detection in disk surface images for disk forensics

In disk forensics application, the goal is to determine whether a particular floppy disk was recorded in a particular drive. This paper discusses how image processing is used to determine whether a disk was recorded in drive A or drive B. Microscope images of floppy disk surfaces are used to extract features. Each image exhibits tracks and gaps as parallel shallow arcs, and the track and gap widths are extracted as features. We apply an image processing method to the shallow arcs to extract their widths. The Hough transform (PVC Hough, 1962) and the concept of entropy are used to segment each arc, and a simple and unbiased parabola fitting is used to fit a circle to the arc segment. Results show this method extracts track and gap widths of real images successfully resulting in the two floppy drives being distinguishable.