The Research On Iteration Algorithms Of Image Reconstructions In The Regions Of Interest Based On The Differential Back Projection

ABSTRACT:Because of the physical limitation and other factors, the reconstruction in the region of interest has always been the focus. In this thesis we mainly study the reconstruction on single photon emission CT(SPECT). Different from the general Radon Transform, there is attenuation in SPECT, so it changes to the exponential one. Inspired by the latest research in the X-CT field, we propose a DBP-Landweber reconstruction based on the prior knowledge. First, based on the relationship between the Hilbert transform and the differential back-projection, we study the condition of complete reconstruction and prove that a discrete Hilbert transform converges to the corresponding continuous case in Lp-norm, then we propose a landweber iterative algorithms. The numerical experiments verify the effectiveness of the proposed algorithms.