Accurate Multimodal Calibration of Portable X-ray Capture Systems for 3D Reconstruction

We describe a method for non-invasive, accurate and efficient 3D reconstruction of occluded scenes from a minimal number of X-ray and range scan image acquisitions. The residuals of generalised epipolar constraints (GEC) are incorporated in an efficient bundle adjustment minimisation, which obtains maximum likelihood estimations of the X-ray image calibration parameters from correspondences between scene points, image points and apparent image contours of scene objects. Furthermore, we make use of a multimodal template adequate for accurate joint calibration of X-ray and range scan images, which offers crucial advantages for security applications such as minimal scene occlusion and an agile data acquisition. Finally we describe a state of the art shape-from-shilhouettes method to retrieve the 3D shape of scene objects by fitting a parametric model shape to their apparent silhouettes. We demonstrate the practical and computational advantages of the method herein described with respect to previous proposals using both synthetic and real experiments.JRC.E.8-Nuclear securit