1. A method of print defect detection comprising: generating a plurality of detail maps of each of a reference image and a scanned image at each of a plurality of resolutions to derive the plurality of detail maps of each image; breaking each detail map of each image into blocks of equal image proportion; calculating an activity measure of each block in each of the detail maps; and calculating similarity measure between the blocks of reference image detail maps and the respective blocks of the scanned image detail maps.