A method for generating a volume-viewing image on the basis of three-dimensional image data of the interior of a body generated by way of a medical imaging system is described. In at least one embodiment, a plurality of different functional structures of the body are first of all segmented in the three-dimensional image data. Moreover, structure selection data for fixing functional structures to be visualized is determined. Then, at least one volume-viewing image is generated from the three-dimensional image data on the basis of the segmented functional structures and the structure selection data and the image is output. Moreover, in at least one embodiment, an image-processing system to carry out at least one embodiment of the method is described.