1. A method for compensating for distortion in a thermal image of a moving object due to non-uniform motion of the object, with the thermal image formed by a thermal scanning system including a fixed infrared scanning device for forming images of part of an object within its field of view and with the infrared scanning device providing a signal output to a computer which executes program code to form a thermal image of the object and calculate temperature values of portions of the object, said method comprising the steps of: fabricating a calibrator object having thermal zone boundaries marked by a contrasting thermal imaging material; transporting the calibrator object across the field of view of the infrared scanning device; executing program code to process signal output from the infrared scanning device to form a thermal image of the object, with images of zone boundaries marked by the imaging material distorted in the image due to non-uniform motion of the calibrator object while the image is being scanned; executing program code to form a window over part of an image and responsive to user commands to draw an outline of a non-rectangular distorted zone and to store coordinates of the outline of the non-rectangular distorted zone; and executing program code to utilize stored coordinates of the outline of the non-rectangular distorted zone to compute temperature parameters from image points included within the outline of the distorted zone.