Abstract: There is disclosed a resolution conversion apparatus for converting an original digital image into a digital image having a different number of pixels in accordance with an instructed conversion magnification factor. In the apparatus, a determination circuit determines the number of pixels to be interpolated in each block of the original image and positions where they are interpolated in accordance with the conversion magnification factor. The block includes a predetermined number of pixels of the original image. A converted image generation circuit generates pixel data for the interpolation pixels at the positions where they are interpolated in accordance with a predetermined interpolation equation whose coefficients are determined with the positions and data values of the pixels in the block, and combines the pixel data for the digital original image and the generated pixel data to output a converted digital image. The interpolation equation includes spline functions and Bezier functions.