Image processing apparatus, image pickup apparatus, and image processing method that use a super-resolution technique for generating a super-resolution image

An image processing apparatus includes: a high-pass filter that extracts a high-frequency component of an input image; an edge judgment unit that judges whether there is an edge based on the high-frequency component and estimates an edge position when there is an edge; a coordinate conversion unit that obtains an edge position in an enlarged image corresponding to the estimated edge position; an interpolation unit that obtains, regarding a position where an edge position of the high-frequency component and the edge position of the enlarged image overlap, a pixel value at each pixel position of an edge circumference of the enlarged image using a pixel value of the high-frequency component; a first enlargement processing unit that generates the enlarged image by enlarging by a desired enlargement factor; and a synthesis unit that synthesizes the interpolated pixel value of the high-frequency component and the pixel value of the enlarged image.