Distinguishing Painted Art from Photographs

Is it difficult do distinguish paints from photos? ... Judge it yourself.

How did we do it?

We have isolated a number of features that are pertinent to paintings more than to photographs (or vice versa) and combined them with a non-linear classifier.

Feature 1: Pure color edges and pure intensity edges

The color edge pixel is a "pure color edge" pixel if it is not an intensity edge pixel. The same goes for the "pure intensity edge". Overall we have found that paintings contain more "pure color edges", that is the variations of color are mastered more as a technique by artists then the variations in light intensity.

Feature 2: Saturation histograms

Feature 3: Spatial variation of color

Feature 4: Gabor filter average response

In the graph below red line is paintings and blue line is photographs. X-axis is 4 filter orientations (from 45 to 135 deg). Y-axis is the average filter response for each class.