Adaptive filtered-back-projection for computed tomography

Joseph Shtok, Michael Elad, Michael Zibulevsky
2008 2008 IEEE 25th Convention of Electrical and Electronics Engineers in Israel  
We propose an extension of the Filtered Back-Projection (FBP) algorithm for reconstruction of attenuation images in Computed Tomography (CT). In our scheme, the standard filtering of projections with windowed ramp kernel is replaced by an adaptive, spatially-variant linear filter, based on a structured bank of 2D convolution kernels. In addition, the proposed scheme includes a post-processing step of image filtering by convolution with a 2D adaptive filter. Both filters are trained for
more » ... reconstruction task via an optimization of corresponding objective function. The reconstruction task is defined through (i) a representative set of specific family of images; (ii) data acquisition conditions (partial set of projections, noise level); and (iii) a Region-Of-Interest (ROI) to be recovered. The resulting adaptive scheme absorbs various imperfections of reconstruction algorithm and specializes to given task, effectively improving the reconstruction quality.
doi:10.1109/eeei.2008.4736585 fatcat:hwbnpb3mrfburpsnps4ewrqjl4