All of Multiline's vision based punching machines operate on very similar principles. A black and white CCD camera is used to view an image of a target. The image sent from the camera to the video system is called a "grayscale." This means that the image is displayed in 256 levels of gray, where a level of 0 is pure black and a level of 255 is pure white. Because the target locating algorithms used in the PE punch systems can only use images in black and white, this image is then "binarized." In the binarization process,a threshold level of gray, is chosen. This threshold level is known as the Sensitivity. All levels of gray in the image which are below the threshold are considered to be black, and all levels at or above the threshold level are considered to be white. The black and white image that results from the binarization process is then broken down into horizontal video lines. In 3000 Vision Systems, each line is analyzed for margin and chord data. The margin is the distance from the edge of the field of view to the edge of the target along a specific horizontal video line. The chord is the distance from one edge to the opposite end of the target along a specific horizontal video image.

The margin and chord data is then used to calculate the location and circularity of the targets. In the newer 3500 Vision Systems, a simple frame grabber sends the grayscale image to the computer which determines the end points of the target horizontal video lines. The endpoint information is used to determine the location of the targets.