To review, we have introduced:
You should now be ready for the reconstruction lecture and discussions of filters. Another aim of this presentation was to make you familiar with terms often used in the reading room when the subjects of image quality or image reconstruction are being discussed.
Remember that multiplication in one domain is convolution in the other domain. This will be very helpful when considering filter applications. Also, remember that the Fourier transform of a square wave is the ripply "sinc" function. This should tell you to avoid the use of functions with sharp edges because they will inevitably introduce "ringing" artifacts in the other domain.
Douglas J. Wagenaar, Ph.D., wagenaar@nucmed.bih.harvard.edu