1. A method for detecting a human head in an image, comprising: receiving a depth image; and applying a template to pixels of the depth image to determine a location of a human head in the depth image, wherein the template includes a circular shaped region and a first annular shaped region surrounding the circular shaped region, the circular shaped region specifying a range of a first plurality of depth values, the first annular shaped region specifying a range of a second plurality of depth values, the second plurality of depth values including depth values larger than the first plurality of depth values, wherein the template specifies a second annular shaped region entirely surrounding the first annular shaped region, the second annular shaped region specifying a third plurality of depth values all having the same depth value, wherein applying the template to pixels of the depth image comprises matching the template to a plurality of foreground pixels in the depth image by comparing depth values of the template to depth values of a neighboring group of pixels surrounding an individual foreground pixel, for the plurality of foreground pixels.