In radiology, it is significantly importance to produce adequate diagnostic information at the lowest dose to the patient. A contrast-detail phantom was generally used to study the image quality and the radiation dose for digital X-ray imaging systems. For evaluating the quality of a phantom image, the radiologists are required to indicate the location of the holes in each square in a phantom image. Then, the image quality figure (IQF) of the image can be calculated. However, evaluation by the human eye is subjective as well as time-consuming, and it is different from person to person. In this paper, an image processing based IQF is proposed to automatically evaluate the quality of a phantom image. The experimental results tell that the proposed method is more sensitive than the radiologists. Moreover, a genetic algorithm is provided to compute the most suitable values of the parameters used in the IP-IQF evaluator.
