Multi-resolution contrast amplification in digital radiography with compensation for scattered radiation

In X-ray projection radiography, especially if area detectors are used, scattered radiation can strongly degrade the image contrast. Although the amount of radiation scatter is partly reduced by the use of anti-scatter grids or air gaps, the contrast is mostly still substantially degraded in large areas of the images. Here, the radiation scatter in radiographs is modeled as the sum of a low-pass filtered version of the primary radiation distribution and a residual scatter component. The authors show how the Multiscale-Image-Contrast-Amplification (MUSICA) algorithm for contrast enhancement can automatically remove the degrading effect of scattered radiation on image contrast, by selectively suppressing low resolution components, without significantly affecting the primary radiation distribution at any spatial resolution.