Evaluation of image quality of different media is difficult because of media's different characteristic. Softcopy and hardcopy as research object was taken as research object. An image difference model based on the mixed chromatic adaptation transform was established and a psychophysical experiment was designed to verify the computation result of the model. The results showed that the proposed model performs well in computation of the image color difference from different media, which can be a tool to evaluate image color difference of softcopy and hardcopy.