Research On Well And Fast CT Image Reconstruction Algorithm Based On Region Of Interest

CT technology has became one of the most important technologies in the field of industrial non-destructive testing.Developing a software platform that can reconstruct CT images quickly and well has great significance to the nondestructive testing of industrial CT.Under normal circumstances,the CT testing of the work-piece being detected globally has large amounts of reconstructed data and use long reconstructed time,while people are often interested in the local information with defects.The emergence of defects has a certain degree of randomness,and can not determine the reconstructed area rely on the general reconstruction before the start of the test.Therefore,the paper mainly focuses on the defective region of solid rocket engine model and uses defective part to reconstruct image well and rapidly,the main research contents are as follows:Research analytic reconstruction technology,describe the principle and procedure of equal angle fan-beam filtered back-projection algorithm and isometric fan-beam filtered back-projection algorithm in detail,Use two kinds of fan beam filtered back projection algorithm to reconstruct the solid rocket engine model on the basis of simulation,and then give out the experimental results.Describe reconstruction principle and procedure of algebraic reconstruction technology,explain main factors that affect reconstruction quality and speed of iterative reconstruction algorithm,and then on the basis of ART algorithm,research other iterative reconstruction algorithms such as SART,MLEM,OSEM,and POCS-TVM,introduce the principle and steps of these algorithms.Finally,reconstruct the solid rocket engine on the basis of simulation,compare the reconstruction results of different algorithms and summarize the reconstruction characteristics of each algorithm,verify the feasibility of themethod.Based on global-local thinking,propose the method that uses low-resolution to reconstruct work-piece firstly,then visually selects the region of interest where has defect,finally,uses different iterative reconstruction algorithms to reconstruct the region of interest with high-resolution and verify the feasibility of the method The results of reconstruction for solid rocket engine show that the algorithm saves a lot of time compared with the global reconstruction in the condition of same resolution,which is benefit for industrial practice.