Modeling of inhomogeneous intensity distribution of X-ray source in radiographic images

X-ray bone images are used in the areas such as bone age assessment, bone mass assessment and examination of bone fractures. The computer aided analysis leads to operator independent, subjective and fast results. In this study, inhomogeneous intensity distribution of X-ray source is eliminated from hand radiographic images. This distribution of X-ray source is modeled by two methods: i) Heel effect, and ii) near field effect. Two models are comparatively examined to represent intensity distribution of X-ray source. The parameter of first and second model is estimated by using simplex method and genetic algorithms respectively. Inhomogeneous intensity distribution of X-ray source is corrected for all image pixels retrospectively. Variance values of pixels in the background are computed to test the two methods. It is observed that variance value of pixels in background decreases more by the novel method compared to the other method.