1. A method comprising: extracting, by one or more computing devices, feature points from video frames of a video file; detecting, by at least one of the one or more computing devices, at least one face in at least a first video frame of the of the video frames; inferring, by at least one of the one or more computing devices, the at least one face in a second video frame of the video frames, the inferring based at least in part on the feature points; arranging, by at least one of the one or more computing devices, the video frames into groups; and combining, by at least one of the one or more computing devices, two or more groups to create refined groups, the combining based at least in part on the two or more groups each including one or more video frames having at least one overlapping feature point associated with a detected face or an inferred face.