This program uses the SUSAN operator (Smith and Brady, International Journal of Computer Vision, May 97) to find the corners in an image. A corner (or interest point) is defined as a pixel which has a significant change in intensity in both the x and y direction. This is different from an edge, which has a significant intensity change in only one of these directions. Intuitively, a corner is the intersection of two edges.
findcorners -f inputfile [-m maxCorners] [-t susan Threshold] [-q]
-f: This specifies the image file that corners are to be found in. Currently, you can use GIF, BMP, PGM, PPM, JPG, PNG files. This is a mandatory input.
-m: Allows an automated process to take place and try to find as many corners up to the specified amount.
-t: Rather than using the automated method to generate a certain number of corners, you can perform a single pass with the SUSAN operator using that specified threshold.
-q: Uses the quick option in the SUSAN operator.
-d: Output interim JPG files.
The default is to try and find 400 corners, and the threshold is automatically chosen to achieve this number of corners. By default, the quick option is OFF.
Upon completion, a file that has the same root as the input file and the extension "corners" is produced. In this file is a list of all corner features found. As well, a JPEG image is produced that had the corners drawn in.
e.g. inputimage.pgm --> inputimage.pgm.corners AND inputimage.pgm.corners.jpg