Differences of edge properties in photographs and paintings

We compare the properties of intensity and color edges in photographs of real scenes and paintings. We demonstrate that paintings contain significantly more color-only edges, whereas the amount of intensity-only edges does not differ significantly between the two classes. In addition, color edge strength is significantly higher for paintings. The differences between paintings and photographs are more accentuated when high-resolution, losslessly compressed images are used. These distinguishing features can be used for the automatic differentiation between the two classes of images.