Measurement of the diameter of the imprint based on image processing using MathCAD and the evaluation software of an industrial CT

Abstract

Instead of the real photograph of a certain object its geometrical model was used to determine an unknown parameter (diameter) starting from a known parameter, using image processing. The test example allowed us to vary certain parameters of the digital image to analyse the factors influencing the precision of size determination. Basics of image processing are presented by the use of the Mathcad software. Using the Mathcad software, by a new application of well-known knowledge a method and a program were developed for the approximate determination of the center and radius (diameter) of a circle. Using the processing software of an industrial CT we demonstrated the effect of pixel size and hue level of pictures of various resolutions on the precision of the determined parameter.