How realistic is photorealistic?

Computer graphics rendering software is capable of generating highly photorealistic images that can be impossible to differentiate from photographic images. As a result, the unique stature of photographs as a definitive recording of events is being diminished (the ease with which digital images can be manipulated is, of course, also contributing to this demise). To this end, we describe a method for differentiating between photorealistic and photographic images. Specifically, we show that a statistical model based on first-order and higher order wavelet statistics reveals subtle but significant differences between photorealistic and photographic images.