1. A method performed on a computing device, the method comprising: receiving, by the computing device, information including an image, a face identifier that identifies a face detected in the image, and a set of facial feature descriptors that indicate features of the detected face; analyzing, by the computing device based on the set of facial feature descriptors, features of the detected face, the features including a mouth of the detected face and at least one eye of the detected face; and determining, by the computing device based on the received information and the analyzing, an expression of the detected face.