<title>Derivation of 2.5D image models from one-dimensional x-ray image sensors</title>

Abstract

S X Godber & M Robinson3-D Imaging GroupDepartment ofElectrical & Electronic EngineeringThe Nottingham Trent UniversityBurton Street, Nottingham, NGI 4BU, EnglandABSTRACTThis paper describes on-going research into the development of a 2'/2-D image modelling technique based on the extractionof relative depth information from stereoscopic x-ray images. This research was initiated in order to aid operators ofsecurity x-ray screening equipment in the interpretation of complex radiographic images.It can be shown that a stereoscopic x-ray image can be thought of as a series of depth planes or slice images which aresimilar in some respects to tomograms produced by computed tomography systems. Thus, ifthe slice images can be isolatedthe resulting 3-D data set can be used for image reconstruction.Conceptually, the production of a 2'/2-D image from a stereoscopic image can be thought of as the process of replacing thephysiological depth cue of binocular parallax, inherent in a stereoscopic image, with the psychological depth cues such asocclusion and rotation. Once the data is represented in this form it is envisaged that, for instance in the case of a securityimaging scenario a suspicious object could be electronically unpacked.The work presented in this paper is based on images obtained from a stereoscopicfolded array dual energy x-ray screeningsystem, designed and developed by the Nottingham Trent University group.Key words: X-ray, line-scan, stereoscopic, 2Y2-D,