<title>Self-calibration of a stereo system using matched points: application to biplane x-ray imaging</title>

Abstract

The purpose of this paper is to elaborate a novel method to determine the absolute geometry of a biplane x-ray imaging system, using angiograms acquired daily by the clinician, without any special calibration procedure during the x-ray examination. The approach is based on the minimization of the mean square distance between observed and predicted projections of a set of reference points identified by the clinician on a simultaneous pair of images. The method employed is iterative and needs two views of at least 12 reference points of unknown 3-D positions to converge to the correct answer. Our approach should be particularly useful in clinical applications since it needs very little intervention from the clinician.