(I moved this here from where I originally posted it after realizing the "images resource from JTP" thread was probably the wrong place for it.)I've been reading this paper (
www.cs.dartmouth.edu/farid/publications/apthesis05.pdf) posted on the website of Hany Farid, a member of Dartmouth College Computer Science Department and an expert in digital image forensics.
The paper discusses approaches to image analysis based on a statistically detectable feature of images from digital camera CCDs. Due to the arrangement of red, green and blue color filters on a ccd, there are twice as many green as there are red or blue. The image pixels must be interpolated from the ccd captured data by a process called "demosaicing." (
http://electronics.howstuffworks.com/digital-camera5.htm) Since the arrangement of pixels on the ccd is not equal between red, green, and blue, the pixels created by demosaicing exhibit a mathematical relationship to one another.
This technique involves a first step of identifying the relationships between pixels by creating a probability map. When Fourier transformation is applied to the probability map, an authentic image yields a non-periodic Fourier transform map. Any manipulation at all results in a periodic Fourier transform map displaying dots, or peaks around the center of the map.
This looks like an incredibly revealing technique. A drone photo passing this test would almost have to prove a 99.999% chance of being real. Since it's now a fact the the Raj location is real, and the photos show a real telephone pole, we know the pole is not CGI. If the drone in the raj photos is not a real object, then the image would have to have been manipulated, which would be detectable with this technique.
Take a look at Figure 3.7 (page 63) in the PDF referenced above for an example of what the results of this test would look like. By performing this test on different areas of the photo, it's very clear where the image has been tampered with.
I would love to see the results of this analysis on the raj photos. It would provide almost indisputable proof of authenticity.