1. A method for determining a facial emotion of a user in the presence of a facial artifact, the method comprising: detecting Action Units (AUs) for a first set of frames with the facial artifact; analyzing the AUs with the facial artifact after the detection; registering the analyzed AUs for a neutral facial expression with the facial artifact in the first set of frames; predicting the AUs in a second set of frames; and determining the facial emotion by comparing the registered neutral facial expression with the predicted AUs in the second set of frames.