image volume 10 and thus define the region where the impression of depth shall be generated according to another embodiment the weighting function g t may increase linearly between the starting and ending planes s 1 and s 2 as is represented in fig2 the type of weighting function determines whether the depth effects shall be clearly visible only in greater depth or whether depth effects shall be recognizable already in the foreground fig3 to 5 represent two examples of permuting an original color chart fig3 shows an exemplary original color chart which assigns a color value for each of the three color channels r g and b to each voxel value having for example values between 1 and 128 or 1 and 256 in the depicted example the original color chart is dominated by the r channel and g channel which means that the voxels are colored yellow the combination of red and green in the additive rgb color model which for example is used for monitors results in yellow now fig4 shows a depth color chart generated from the original color chart by permuting the r channel and the b channel the depth color chart therefore is dominated by shades of green and blue this means that the image colored in shades of yellow according.