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.


Default Values:

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