Devices and method are provided that facilitate improved input device performance. Specifically, the systems and methods are configured to identify a portion of an image of sensor values as corresponding to at least one sensed object in the sensing region, determine a polygon corresponding to the identified portion of the image, and determine a contact characterization of the at least one sensed object based on the polygon. The determination of a polygon corresponding to a sensed object facilitates improved contact characterization of the sensed object. For example, the determined polygon may be used to determine if the sensed object is actually more than one object. As a second example, the determined polygon may be used to determine the orientation of the sensed object. In addition, determined polygons may be used to more accurately track changes in the position of the sensed object.