Pixel-driven computation of parallel and fan-beam projections of a digital image based on pixel-representation using a new formula.

Background: The computation of the projections of a digital image - modelled as a superposition of square pixels - is essential in several algorithms in computed tomography, and also in many machine vision applications. Projections of digital images are computed through the ray-driven approach. Current pixel-driven methods, though simpler, involve interpolation kernels in the projection-domain - not based on the exact Radon transform (RT) of a square.

Cone-beam reprojection using projection-matrices.

This paper addresses reprojection of three-dimensional (3-D) reconstructions obtained from cone-beam scans using a C-arm imaging equipment assisted by a pose-determining system. The emphasis is on reprojecting without decomposing the estimated projection matrix (P-matrix) associated with a pose. Both voxel- and ray-driven methods are considered.

Techniques to alleviate the effects of view aliasing artifacts in computed tomography.

Due to practical limitations in data acquisition, 3-D computed tomography systems must attempt to provide rapid reconstructions of acceptable quality from a limited number of views. The use of convolution backprojection (CBP) for image reconstruction from an inadequate number of projections, results in view aliasing artifacts. In this paper we investigate different post-processing methods of alleviating the effects of view aliasing artifacts.