The conflicting demands of minimizing radiation dosage and constant replenishment of the image result in noisy videofluoroscopic image sequences. We are investigating the possibilities for real-time digital image processing to reduce the level of noise without increase in x ray exposure rate. Several approaches have been previously suggested based on combinations of spatial filtration, temporal filtration and grey scale remapping. It is demonstrated that motion adaptive temporal filtration combined with grey scale remapping has considerable advantages. Real-time temporal averaging is conventionally performed by means of dedicated hardware which includes adders, multipliers and, for non-linear processing, comparators. Typically, the algorithm has to be selected before the hardware can be built. Thus, in order to permit a more general experimental investigation a temporal filter using reprogrammable dual-input look-up tables was designed and built.
John A. Rowlands, John A. Rowlands,
"Real-time digital processing of video image sequences for videofluoroscopy", Proc. SPIE 1652, Medical Imaging VI: Image Processing, (1 June 1992); doi: 10.1117/12.59437; https://doi.org/10.1117/12.59437