1. One or more computer-readable media containing instructions to process two or more images for distinguishing a head in the images from other portions of the images, the instructions being executable to perform actions comprising: predicting portions of the images that form facial portions of the images; calculating one or more skin colors by sampling the images at the predicted portions; computing a first mask image that marks any image pixels whose colors are different in the two or more images; creating a second mask image that marks any image pixels whose colors correspond to the calculated one or more skin colors; combining the first and second mask images to create a final mask image.