This paper presents a system, called CollageBild, to create an image mosaic (or collage) by putting together smaller images. The minimum requirement is to have a base image, a set of reference images, and a value for the minimum number of blocks along row or column. Several additional processing parameters are used to control the color model, color distance, and image sampling strategy. The system is described and applied to test cases with a variety of real and synthetic references. The results vary considerably, not only with the parameters setting, but also with the reference images used. There is no ideal result, as the decision of what is the best setting is based on aesthetics.