Identifying Manipulated Images

Jamie found a cool story at MIT Tech Review. (As an aside, it sits behind an interstitial ad AND on 2 pages: normally I reject websites that do that, but it's a slow news day, so I'm letting it through.) Essentially, software is used to analyze light patterns in still photographs. Once you can figure out where the light sources are, it becomes a lot easier to determine if an image has been photoshopped.

Comments

Steganography

[unbug]

Does it also apply to steganography? Would sort of suck if it did.

Goes both ways

[Nerdposeur]

...and then the photoshoppers will write evolutionary algorithms to modify their photographs until they pass evaluation by this tool.

Adds a step for the photoshoppers

[crowemojo]

One would think that it would be simple enough, after finishing whatever touch-ups that you want to perform, that you use this technique to calculate where the light sources should be, and then correct the minute details that would give it away as an altered image. Sounds like the kind of thing that would be a simple photoshop plugin actually, once you are all done you just run the "make undetectable from light source detection analysis" tool and call it a day.

Re:Good

[dotancohen]

That's why I say "to gimp a photo" rather than say "to photoshop a photo". It spreads awareness, breaks the Adobe monopoly, and sounds more natural. Even Adobe discourages the use of "photoshop" as a verb.

Re:Good

[m.ducharme]

Even Adobe discourages the use of "photoshop" as a verb. You know why, right? If they let "photoshop" be corrupted in the language as a verb, they would eventually lose the trademark rights to the name. Eventually, companies would be able to get away with naming their software "MS Photoshopping Program" or "Gimp Photoshop Utility" or whatever, and Adobe wouldn't be able to do anything about it.

Are you sure now, that you want to discourage people from using "photoshop" as a verb?