Kresimir Matkovic László Neumann Attila Neumann Thomas Psik Werner Purgathofer Global Contrast Factor - a New Approach to Image Contrast. 159-167 2005 conf/cae/2005 Computational Aesthetics http://dx.doi.org/10.2312/COMPAESTH/COMPAESTH05/159-167 db/conf/cae/cae2005.html#MatkovicNNPP05