Asymmetries In The Single Image Density Reconstruction Study

The high-energy x-ray radiography is the effective experimental means to detect the compressed state of the hydrodynamics experiment. Because the high-energy x-ray radiography system is complicated, the number of views is limited, and it only can take a single or two radiographs once. In the late compressed state of the hydrodynamics experiment, the density distribution is of evident asymmetry. Therefore, the study of the density reconstruction from a single radiograph is practical significant, especially for the asymmetric objects.Base on image reconstruction theory, high-energy x-ray radiography image reconstruction model is discussed in this paper. The author adopts rectangle gridding method to section segmentation and consummates its corresponding reconstruction equation for ART. Due to the parallel beam, an efficient method to compute projection coefficient is adopted. The reconstruction problem is ill-posed, so the three dimension program for the density reconstruction is developed based on total variation. In this paper, for the asymmetric objects, the author adopts an approach to compose the other rotational views, making explicit use of model-based information concerning the symmetric and asymmetric information from the radiograph.Numerical experiment results show that the approach proposed compose the other rotational views from a single radiograph for the asymmetric objects is effective and the impact on the accuracy of density reconstruction by varying the number of the radiographic views is obtained.