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How Photoshopped Is That Picture?
Freddybear writes "Digital forensics experts at Dartmouth have developed software that can analyze digital photos to rate how drastically they have been altered by digital editing techniques. 'The Dartmouth research, said Seth Matlins, a former talent agent and marketing executive, could be "hugely important" as a tool for objectively measuring the degree to which photos have been altered.'"
It also uses advanced neural-network powered learning algorithms to allow it to also leverage "having seen a a great many shops".
If it did the analysis using just the "after" image (maybe by looking statistically at ithe ndividual pixel level, I dunno I'm not an image expert) that software would be SO useful for Internet dating sites! ;)
Actually I'm wondering if images CAN be analyzed using statistical data from the individual pixel data to determine things like what camera was used to take the picture, maybe what software was used to edit/convert it (using gamma curves?). Then you could see (maybe) who was posting pictures of themselves from long ago (not like I've ever done that!).
Yeah, it shouldn't be that hard to uncrop a picture.
You mean they're promoting a law that would make Victoria's Secret disclose the endless belly-fold-tucking and (B to D) breast enlargements they love so much? As a doc, looking at those anatomically-impossible bodies it makes me sad, because they change our perception of what should be seen as attractive to a standard that is literally impossible to meet. And at times even I have caught my own perceptions as being skewed, despite knowing full well how it happened.
I already exists, it is called "alcohol".
Actually, conversion is one method of detecting photoshop changes. It's called Image Error Level Analysis.
http://errorlevelanalysis.com/
The gist is that every time you save an e.g. JPEG, the quality will get worse. However, the worsening of quality decreases each time it is saved, eventually asymptotically approaching the worst level. Therefore, if you're working on a photoshopped picture, each time you save it the quality of the various parts of the photo will decrease by different amounts. This can be used to identify which pieces of the photo have been modified more recently than others, since they will have a different error level than the pieces that were modified first.
:(){
I bet the people on CSI can uncrop a picture. ;)
If I were God, wouldn't I protect my churches from acts of me?
Counterpoint: The property owners aren't the market for these images, their potential tenants and customers are the market.
For example, when you're viewing images of hotel rooms on-line:
http://www.fourseasons.com/
Even the image on the landing page has been retouched. If you were taking a picture down an outside corridor like that, you would either blow-out the highlights and have a dark grey blob where the tree is, or you would under-expose the shadows and not see the corridor at all. That image is a composite of at least two images taken with different f-stops and probably different shutter speeds.
http://www.fourseasons.com/accommodations/
See that room? See the Hong Kong sky-line? Notice how the exposure on both the room and the outside are perfect? Notice how the exposure on everything in that room is perfect? Even with good lighting equipment you can't get that sort of perfection with a single exposure. Go look at any other hotel site and notice their pictures too. That takes time and expertise.
The point of all of this? Marketing and advertising. Even paying someone like I've mentioned a couple of thousand for some really excellent images is worth it when you're selling million dollar condos or multi-million dollar office spaces. If you can close on a property even 10% faster due to a really well done image, that's 10% more time you have to find and move other properties. Time==Money and people are swayed by advertising images all of the time.
When was the last time you ordered food because it looked damn good on the menu?
When was the last time you listed after a car, or gun, or other piece of hardware because it looked so god damn cool?
When was the last time a picture of someone in a magazine or ad got your blood pumping and hormones raging?
Advertising.
I recently got a tiny point-and-shoot camera, a Canon ELPH 300 HS, and I've been participating in CHDK's effort to hack it. When we got RAW support working, I learned the camera's lens actually has severe barrel distortion that gets "corrected" in software before saving a JPEG.
Images are "shopped" before they even emerge from the camera these days.