1. An image processing apparatus comprising: a detection unit configured to detect a frame rate of a moving image; a resolution increasing unit configured to, using images of a plurality of frames including a target frame of the moving image, generate a high-resolution image having a resolution higher than that of the target frame; and a determination unit configured to determine, based on the frame rate detected by said detection unit, the number of the plurality of frames to be used by said resolution increasing unit, wherein said determination unit increases the number of the plurality of frames to be used by said resolution increasing unit as the frame rate detected by said detection unit rises.