1. A method, comprising: identifying, by a computing device, two or more individual regions in a digital image that each include a face; assigning, by the computing device, a fitness score to each of the two or more individual regions, wherein a fitness score for a particular region is based on a facial expression characteristic of the face corresponding to the particular region and an exposure amount of the face corresponding to the particular region, and wherein the facial expression characteristic comprises a gaze direction; defining, by the computing device, a combined region based on the fitness score, wherein the combined region includes the two or more individual regions, wherein a border of the combined region is collinear with a border of one of the two or more individual regions; determining, by the computing device, an average gaze direction based on the gaze direction of faces associated with the two or more individual regions; and defining, by the computing device, a gaze region that is based on the average gaze direction.