8.6Convolution backprojection
Once we have an FBP algorithm, there should be no problem at all to obtain a convolution backprojection algorithm. All we have to do is to take the inverse Fourier transform of the weighted ramp filter to get a convolution kernel.
This is easier said than done. The problem is that we have a closed-form expression for the frequency domain transfer function for the windowed ramp filter; however, we do not have a closed-form expression for the spatial domain convolution kernel. Numerical evaluation of the convolution kernel costs time.
Fig. 8.6: FBP reconstruction results using dynamic MRI data. Top: Reconstructions ...
Get Image Reconstruction now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
