1. A computerized method for automatically classifying videos based on faces discovered in the videos, wherein the discovered faces are not known to be associated with a particular category of videos, the method comprising: receiving, by a programmable processor, a video for classification; detecting, by the programmable processor, a face of a person in the video; determining, by the programmable processor, that the detected face is not associated with a set of known people stored in a database of known persons that is in communication with the computing device, wherein each known person from the set of known people is associated with one or more categories that can be used to classify videos in which the known person appears; comparing, by the programmable processor, the detected face to a set of unknown faces in an database of unknown faces in communication with the programmable processor, to generate a cluster of unknown faces that each match with the detected face by meeting a predetermined match threshold; identifying, by the programmable processor, a set of categorized videos based on the cluster of unknown faces; and assigning, by the programmable processor, one or more categories to the video based on categories associated with the set of categorized videos so that the video can be automatically classified based on the detected face even though the detected face is not associated with a known person.