Abstract: An image reconstruction system and method based on image projection data collected by an imaging system having N tubes of response (TORs) having N? axial translation symmetries and N? in-plane rotation symmetries between the TORs. A system matrix mapping image projection data to pixels of an image is used, where the pixels are positioned according to a polar or cylindrical coordinate grid. During image reconstruction, matrix-vector computations are performed between the system matrix and vectors containing image estimates or image projection estimates. The matrix-vector computations are accelerated by structuring the system matrix coefficients, image vectors, and projection measurement vectors in such a way that symmetric data is stored in contiguous memory locations.

Abstract: An image reconstruction system and method based on image projection data collected by an imaging system having N tubes of response (TORs) having N? axial translation symmetries and N? in-plane rotation symmetries between the TORs. A system matrix mapping image projection data to pixels of an image is used, where the pixels are positioned according to a polar or cylindrical coordinate grid. During image reconstruction, matrix-vector computations are performed between the system matrix and vectors containing image estimates or image projection estimates. The matrix-vector computations are accelerated by structuring the system matrix coefficients, image vectors, and projection measurement vectors in such a way that symmetric data is stored in contiguous memory locations.

Abstract: An iterative image reconstruction method used with an imaging system that generates projection data, the method comprises: collecting the projection data; choosing a polar or cylindrical image definition comprising a polar or cylindrical grid representation and a number of basis functions positioned according to the polar or cylindrical grid so that the number of basis functions at different radius positions of the polar or cylindrical image grid is a factor of a number of in-plane symmetries between lines of response along which the projection data are measured by the imaging system; obtaining a system probability matrix that relates each of the projection data to each basis function of the polar or cylindrical image definition; restructuring the system probability matrix into a block circulant matrix and converting the system probability matrix in the Fourier domain; storing the projection data into a measurement data vector; providing an initial polar or cylindrical image estimate; for each iteration; reca

Abstract: An iterative image reconstruction method used with an imaging system that generates projection data, the method comprises: collecting the projection data; choosing a polar or cylindrical image definition comprising a polar or cylindrical grid representation and a number of basis functions positioned according to the polar or cylindrical grid so that the number of basis functions at different radius positions of the polar or cylindrical image grid is a factor of a number of in-plane symmetries between lines of response along which the projection data are measured by the imaging system; obtaining a system probability matrix that relates each of the projection data to each basis function of the polar or cylindrical image definition; restructuring the system probability matrix into a block circulant matrix and converting the system probability matrix in the Fourier domain; storing the projection data into a measurement data vector; providing an initial polar or cylindrical image estimate; for each iteration; reca