Image continuity at different levels of zoom for Moiré techniques

摘要

Moiré technique is a technique used for 2D and 3D imaging and surface characterization. Moiré systems may have a range of zooms to image an object at different levels of details or Moiré images may be combined (or compared) with images from other interferometers. So, it is needed to inter-relate images together in order to keep the continuity of the images at different levels of zoom or images from different types of interferometers. This paper uses image registration techniques to correlate images and fïnd scale and translation between two images. Image registration is widely used in medical imaging and range imaging to relate two different images from a single object or scene. In this work, only interferograms from two successive levels of zooms of a Moiré system are used. Saved interferograms are correlated using one of the affme algorithms which are used in image registration and then relative scale and shift are calculated. Calculation of these parameters makes it possible to locate the position of area that the Moiré system is zoomed in, related to the area with lower zoom level. Simulation results show that this technique is applicable and successful in finding the scale and shift parameters within the resolution of one pixel and therefore can keep the continuity between images at different levels of zoom.