1. A video categorization method, the method comprising: acquiring a key frame from a video, the key frame comprising an image including a face; acquiring a face feature from the key frame of the video; acquiring one or more face features that correspond to one or more respective picture categories; selecting a picture category to which the video belongs based on the face feature from the key frame and the one or more face features corresponding to the one or more respective picture categories; assigning the video to the picture category to which the video belongs; wherein the acquiring the key frame from the video comprises: acquiring, from the video, at least one video frame comprising one or more faces, determining a face parameter for each of the at least one video frame, the face parameter comprising either or both of a face quantity and a face location, and determining the key frame from the video, based on the face parameter for each of the at least one video frame; and wherein determining the key frame in the video according to the face parameter for each of the at least one video frame comprises: determining, according to the face parameter for each of the at least one video frame, one or more non-duplicate video frames each having a face parameter that does not reoccur for other video frames, and selecting at least one of the non-duplicate video frames as the key frame.