Abstract: A method is presented for detecting visual artifacts such as macroblocking artifacts appearing in a rendering of a video stream. A decoded video stream that includes a plurality of frames is received. Edges appearing in the plurality of frames are detected and data characterizing the edges is directed to a neural network. The neural network determines a likelihood that a macroblocking artifact occurs in the video stream using the neural network. The neural network is trained using training data that includes (i) one or more video sequences having known macroblocking artifacts whose size and duration are known and (ii) user ratings indicating a likelihood that users visually perceived macroblocking in each of the one or more video sequences when each of the one or more video sequences are rendered.