6. The process of claim 5 , wherein the determined presentation style comprises a one of the presentation styles in a set of possible presentation styles comprising: a rendered video class of presentation styles; and a real-world video class of presentation styles.
5. A computer-implemented process for identifying the presentation style of a video, comprising the actions of: using one or more computing devices that are in communication with each other via a computer network to perform the following process actions: receiving the video; computing a set of face features that represent the video, wherein the face features are based on the detection of one or more faces in the video, the face features comprising one or more of, a face detection feature measuring the percentage of frames in the video where just one face is detected, or one or more moving face features each measuring, for each frame of the video where just one face is detected, whether or not said detected face is moving, or a face not present feature measuring the length of the longest sequence of frames in the video where no face is detected, or a face present feature measuring the length of the longest sequence of frames in the video where just one face is detected, or a face size feature measuring, across the frames in the video where just one face is detected, the average size of said detected face; and using a pre-learned video presentation style classifier to weight each of the face features in said set and determine a presentation style that is predominately employed in the video, said presentation style determination being based on the weighting of said features.