Research Of Dual-energy X-Ray Material Identification System

X-ray can nondestructively penetrate materials and it has high recognition,therefore it is widely used in the imaging tests of medical,industrial inspection,energy survey security,and other fields.With the emergence of a variety of photographic device,costs of X-ray detection systems are coming down,and the imaging quality is improved,the test results are from a single object shape recognition to the study of material properties.Dual-energy X-ray material identification technology is one of the important developments for X-ray imaging applications.This paper will introduce a portable dual-energy X-ray material identification system based on flat panel detector.According to the procedure of system design,there are the introductions of the theory of dual-energy X-ray material identification technology,the system composition,related image processing algorithms,material identification method and the development of software system.First of all,introduce the origin and development of dual-energy X-ray material identification technology,and the domestic and foreign research situation.Secondly,research basic theory,infer the attenuation law from analyzing the interaction between materials and X-ray,and calculate the value R which is related to effective atomic number of material,we can identify material category from this value.Then campare the commonly used dual-energy X-ray detection equipments at present,and choose a portable pulse variable voltage X-ray machine as radiation source,chose flat panel detector as image detector,these constitute the true dual-energy system solution.The image preprocessing of this system is executed from two aspects:flat panel detectors calibration and image segmentation.This paper proposes a multiple threshold image segmentation algorithm optimized with edge detection operator.Through the study of traditional material identification methods,this paper puts forward a kind of undersampling material classification method with extracting value R to create a mapping template image,and process it with multi-threshold segmentation algorithm.Based on the image segmentation,two color schemes based on the pattern of the RGB and HSI are designed and compared.Finally,develope a feature-rich application software with complete structure,and finish the design and implementation of the system.