1. A method of operating an interactive input system comprising: capturing images of a region of interest at a first frame rate when the interactive input system is operating in a standby mode; processing a first pixel subset of images captured at the first frame rate to detect a presence of an object; if an object is detected, capturing images of the region of interest at a second frame rate; processing a second pixel subset of images captured at the second frame rate to determine if the object is a pointer; in the event the object is a pointer, operating the interactive input system in an interactive mode, wherein operating the interactive input system in the interactive mode comprises capturing images of the region of interest at a third frame rate; and processing a third pixel subset of images captured at the third frame rate to determine the location of the pointer, wherein the first pixel subset comprises a first number of rows of each image captured at the first frame rate, wherein the second pixel subset comprises a second number of rows of each image captured at the second frame rate and wherein the second number of rows is greater than the first number of rows.