An understanding of digital radiography through image computer simulation

A set of computer models has been developed to generate images simulating those produced by projection x-ray systems. This was done to aid in the understanding of required sub-system performance and to study the implications of various system designs. For this purpose the basic processes of x-ray generation, attenuation and absorption were modeled. Scatter-to-primary ratios were modeled using published experimental data. A random number generator is used to model quantum as well as other sources of noise. These computer models agree well with experimental measurements. These image simulation programs have been used to predict the performance of digital radiographic systems (both scanned fan-beam and fluorographic). Images of both temporal and dual energy subtraction will be presented. The effects of x-ray spectrum shaping, scatter-to-primary ratio, QDE, veiling glare and electronic noise will be shown. The detection of simulated vessels containing low amounts of iodine by the various system alternatives will be compared.