A method and apparatus for generating a color reference for an image to be printed for visualizing the same on a true-color monitor is disclosed. Lower-resolution image data are generated from high-resolution raster data for the image to be printed which are obtained from page description data for the image to be printed. The lower-resolution data are converted into display data which serve as color reference for the image to be printed and which can be visualized on a true-color monitor. An actual transmission characteristic is ascertained. The actual transmission characteristic ascertained is compared with a specified (desired) transmission characteristic, where, on the basis of this comparison, a correction curve is calculated which is required to arrive at the desired transmission characteristic starting with the actual transmission characteristic. The display data are ascertained using the calculated correction curve.