A receiving apparatus receives a hierarchically encoded image signal and detects an error in the image signal. Then a filter process is performed on the image signal, the filter process being controlled based on the output of the error detections. More particularly, the image signal has multiplexed therein a first encoded image signal having a lower image quality and a second encoded image signal for obtaining a higher image quality. These are decoded to obtain a first decoded image signal and a second decoded image signal, and the position of an error in an image frame of the image signal is detected. Then a mode of the apparatus is set to one of a plurality of modes according to the detection, the modes including a first mode in which an image signal having the higher quality is obtained by synthesizing the first and second decoded image signals and a second mode in which an image signal having the lower image quality is obtained by inhibiting a synthesizing operation of the second decoded image signal to the first decoded image signal.