An image interpolating method for interpolating a pixel at an intermediate position
between a first original pixel and a second original pixel adjacent to the first
original pixel, comprising a first step of calculating an edge component for judging
whether or not an interpolated pixel is positioned in the vicinity of an edge position
of original image data, a second step of determining a range where pixel data on
the interpolated pixel is settable on the basis of the calculated edge component
and pixel data on the first and second original pixels, and a third step of selecting
a plurality of sets of opposed pixels between which the interpolated pixel is sandwiched
diagonally, and determining, for each of the sets, the pixel data on the interpolated
pixel in a case where a correlation value represented by the sum of the absolute
values of the differences between the pixel data on the interpolated pixel and
pixel data on the opposed pixels is the minimum in the range where the pixel data
on the interpolated pixel is settable and the minimum correlation value.