A sequential-scanning process with motion information that compensates for inadequate motion estimation and motion compensation that would otherwise cause degradation of images, by correctly detecting errors arising from operations of motion estimation and compensation. Horizontal and vertical (filtered) patterns of each of motion-compensated (MC) and spatial-interpolated (SI) images are compared. If there is an error in the procedure of motion estimation, the process is carried out with a mixed (weighted) combination of the motion compensation and spatial interpolation or with the spatial interpolation only, instead of the motion compensation.