Identifying Manipulated Images

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• 	Apollo mdale9 on 03/17/2008 at 4:04 AM
  Posts: 2 Avg Rating:	I would be nice to use this tool to determine if any of the Apollo moon landing photos were faked.  Theoretically there should only be a single light source, shouldn't there? Rate this comment: (Reply)

  • Re: Apollo nealkrawetz on 03/17/2008 at 10:36 AM

    Posts: 3 Avg Rating:

    Hi mdale9, There is one primary light source (the Sun), but there should be lots of ambient light of varying degrees (stars and reflection of any earthlight). As far as analysis goes, there is usually no difference between a "real" and "staged" photo -- both are "real" in that they were not digitally manipulated. However, this does not mean that the content is real. For example, Imad Mughniyeh staged the famous photo of him holding a gun to a pilot's head (http://edition.cnn.com/2008/WORLD/meast/02/13/btsc.clancy.mugniyah/index.html). The interpretation of the photo's content is deceptive but the image itself is real. When you ask about the moon landing, the photos that I have looked at appear to be real. However, I will not to get into a debate on whether they were staged or actually taken on the moon -- too many people ignore facts in place of agendas and conspiracies. - Dr. Neal Krawetz Rate this comment: (Reply)

  • 	Re: Apollo smithsomian on 03/19/2008 at 11:42 AM
    Posts: 18 Avg Rating:	The surface of the Moon is lightly-colored and, with no atmosphere, subject to brilliant light from the sun - how can you say there's only one light source? Rate this comment: (Reply)

• 	Identifying Manipulated Images deejay on 03/17/2008 at 5:15 AM
  Posts: 22 Avg Rating:	I'm curious - is this only for digital photographs, or will it work with a film-based photograph that has been scanned and digitised? Rate this comment: (Reply)

  • 	Re: Identifying Manipulated Images Erica Naone on 03/17/2008 at 9:03 AM		TR Staff Assistant Editor
    Posts: 26 Avg Rating:	My understanding is it would work with scanned and digitized photos as well as photos that were originally digital. -- Erica Naone Rate this comment: (Reply)

  • 	Re: Identifying Manipulated Images nealkrawetz on 03/17/2008 at 10:17 AM
    Posts: 3 Avg Rating:	Hi deejay, It depends on the type of manipulation. Light direction may still be detectable, as will any poorly pasted borders. However, my tools also look for compression artifacts and format anomalies. These will not be present if a photo is manipulated before being digitized. - Dr. Neal Krawetz Rate this comment: (Reply)

• 	New moon & mars pictures dsouza on 03/17/2008 at 12:01 PM
  Posts: 1 Avg Rating:	Is this tool available somewhere, or is it source closed ? I think it would be nice to test the images on the new moon images (specially those from the chinese probes) and the mars pictures (which are said to be [color-]tampered, although maybe it wouldn't work for color tampering detection). Rate this comment: (Reply)

  • 	Re: New moon & mars pictures Erica Naone on 03/18/2008 at 10:04 AM		TR Staff Assistant Editor
    Posts: 26 Avg Rating:	At this point, neither of the tools mentioned in the article are publicly available, as far as I'm aware. I should also note that, while other digital forensics tools might detect color changes, tools that pay attention to lighting (which I've focused on here) seem best suited to flagging cases where multiple photos have been combined into one. -- Erica Naone Rate this comment: (Reply)

• A picture can be a thousand lies. gabrielg01 on 03/18/2008 at 12:17 PM

  Posts: 305 Avg Rating:

  Even if such software tools are available, one could still produce fake images. As a forger, you would take the fake image and run tests on it with the forensics software, and see which part of the image is flagged as fake. Then you modify the image accordingly, and test again. A few iterative steps like these, and you would be able to produce an image that passes the test. Sure this means more work on the part of the forgers, but then they can claim to have a "genuine" picture. We should never rely solely on pictures as proof anymore. A picture can tell a thousand lies. Rate this comment: (Reply)

  • 	Re: A picture can be a thousand lies. Erica Naone on 03/19/2008 at 9:39 AM		TR Staff Assistant Editor
    Posts: 26 Avg Rating:	You're absolutely right. However, when I asked Johnson about this, he pointed out that, for now, forgers tend not to have access to these tools. It'll be a different game once they're packaged with Photoshop. One additional point is that, like all questions of security, if someone is intent on pulling off a beautiful and sophisticated forgery, and has the skills to back that up, they probably can. However, many forgeries simply aren't done with that level of dedication and skill, and tools can help filter out those forgeries. Rate this comment: (Reply)

    • Re: A picture can be a thousand lies. nealkrawetz on 03/19/2008 at 12:30 PM

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      One of the things I mentioned at my Black Hat Briefings talk was specifically about the necessary skills. The tools are widely available -- Photoshop, Gimp, 3DS Max, Maya, Bryce, etc. either come with your system (or camera or scanner) or can be purchased as off the shelf software. Having the tools is not difficult. However, having the skills to use the tool is a different story. (Just because I own a hammer does not mean I can build a house.) Most people who modify images lack the skills to overcome most image analysis techniques. In fact, many forgeries by professional artists still test positive for being modified. My own tools are around 86% accurate. The few misses were by professional artists who have won awards from the CG Society. And two of the misses were by the same artist who spent over two years on the same model (wireframe, skin texture, hair, etc.). Fortunately for detecting forgeries, most amateurs don't have the skill or time to devote to their edits. (Even I, knowing exactly how the tools work, cannot make a good forgery because I lack the skills to use the drawing tools at a professional level.) Given enough time, an amateur artist should be able to defeat a few of the detection methods. However, I use a suite of analysis tools and methods -- light analysis is just one approach. Very few doctored images can make it past all of the tests, and those that do were likely by professional artists who have plenty of time to devote to the forgery. You are correct that a professional forger could use these forensic techniques to better the forgery. Fortunately, most doctored images are not by professionals, and even professionals may not have the time to overcome all of the signs of modification. There is a saying in the computer security field: the defender has an impossible task; they must defend against all possible attacks, while the attacker only has to find one vulnerability. The same can be said about photo forensics: the forger must hide all possible signs of modification or forgery, while the forensic examiner only needs to find one clue. Rate this comment: (Reply)

• 	Identifying Fakes jmaximus9 on 04/04/2008 at 9:22 PM
  Posts: 34 Avg Rating:	Now if we could figure out a way to tell when Hillary is lying; oh yeah thats right we did, when her lips are moving. Rate this comment: (Reply)