Design and realization of filtered backprojection algorithms of CT image reconstruction based on FHT and MSBP / 医疗卫生装备

ABSTRACT

Filtered backprojection algorithms are widely used in the commercial CT systems.The projection data and the object functions all belong to the real number area in applications of CT image reconstruction.The reconstruction algorithm based on Fourier transform involves lots of complex number operations.It's an inherent characteristic in computation.Because of the real number transform characteristic of Hartley transform comparing with Fourier transform,the signals and images in the real number area can be processed using Hartley transform instead of Fourier transform.Based on the geometrical relationships between image pixels and projection rays at different viewing angles,a Multi-orientation simultaneous computation of backprojection for tomographic image reconstruction(MSBP) approach is proposed.In this paper,the filtered backprojection algorithms of CT image reconstruction are realized by using FHT and MSBP.The algorithms may lead to the reduction of the memory space and can reduce the amount of calculation while retaining the precision.