1. A computing system comprising: an infrared (IR)-absorbing surface; an IR camera disposed above and pointed at the IR-absorbing surface to capture an IR image representing an object disposed between the IR camera and the IR-absorbing surface based on IR light reflected by the object; an RGB camera to capture an RGB image representing the object disposed between the RGB camera and the IR-absorbing surface; and a segmentation engine to determine a segmentation boundary representing at least one outer edge of the object based on the IR image and the RGB image.