The object of the invention is to convert a low-quality original image into a
high-quality fractal-interpolated image. From a low-quality original image, original
image blocks of nn size, which are mutually overlapping and each centered
on each pixel of the original image, are acquired. Also, similar image blocks of
2n2n size, which are each similar to each of the original image
blocks, are detected from the original image by affine transformation. The detected
similar image blocks are reduced to the same size as the original image blocks,
and then substituted for the original image blocks respectively. Then, overlapping
portions of the substituted similar image blocks are adjusted by averaging. As
a result, a high-quality fractal-interpolated image is generated.
