The authors provide an image to image filter sufficient to do discrete fourier reconstruction of sinogram to image data.  The filter has parameters to adjust the reconstruction to allow for image padding, resampling, and interpolation order.  In addition, the authors provide a Bspline interpolation class for complex data.

The hypothesis is that they can support direct FFT tomographic reconstruction in the ITK environment for parallel beam CT sinogram data.

The authors provide a code implementation and a test input/output image pair that provide evidence the filter works as described.

Source code for the reconstruction algorithm, the bspline interpolator, and test drivers are provided; as are input and output images.

I downloaded, compiled and ran the code.  The code passed their test and manual comparison of the target output image to that generated by the provided code gives qualitatively identical results.  The provided paper provides a good overview of the algorithm and sufficient detail so as to understand the provided code.

There was one small compilation error under VS9 where the compiler was unable to properly determine which atan function (float atan(float) or double atan(double)) at line 27 of itkDirectFourierReconstructionImageToImageFilter.txx.  By making the provided argument a double, this compilation error was removed.

Data is derived from a standard phantom and is easy to use.