Overview

PerCor is a simple programme for the rectification of perspective distortion. It requires two images along with a set of matching points (control points) for each. A single image may also be used and corrected arbitrarily to create a new image of the same size.

Open a either a pair of images (usually one will be a map or an othophoto, the other an oblique aerial photo, or any other related image pair) using one of the many supported file formats.



















Enter corresponding control points in both images using one or more of the control point entry techniques described elsewhere.

Transform the image to the map:



















or to a blank image of scaleable size, or if no map is used, to a blank image of size equal to the original image.  

This technique is useful for correcting distortion in images of oil paintings or paintings under glass which have been photographed using a camera flash at an angle to avoid reflections or when a suitable position for the camera for a non-distorted result is unavailable:



















to:



















Save the result to a new file for use in other programmes. 

Print the result if desired.

All programme operations are carried out using the mouse, the toolbar and the menus.