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Digital Camera Image Verification
Polo writes "While reading dpreview, I noticed that among several new products, Canon has announced a Digital Image Verification Kit to prove that an image taken by a particular camera has not been modified. It's disturbing to think about the conditions that would allow digital images to be accepted in a courtroom. I guess one defense would be to figure out how to 'verify' a photo of shark attack..."
The kit consists of a dedicated SM (secure mobile) card reader/writer and verification software. When the appropriate function (Personal Function 31) on the EOS-1D Mark II or EOS-1Ds is activated, a code based on the image contents is generated and appended to the image. When the image is viewed, the data verification software determines the code for the image and compares it with the attached code. If the image contents have been manipulated in any way, the codes will not match and the image cannot be verified as the original.
So it's basically an MD5 (or equiv hashing method) of the image at the time it's taken? Too bad -- I thought they had a unique idea to verify images that had already been taken.
Two or three questions I suppose:
All in all I suppose it's a neat idea -- hope it actually works before somebody is on trial for his life though...
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
1.) Take picture :-)
2.) Photoshop picture
3.) Print picture
4.) Take picture of printed picture
It won't work. From everything I've seen, attempts to verify ANYTHING digital will be cracked within a week or three.
I'm willing to be that one of the first customers for this software is the tabloid newspapers/magazines. They pay small fortunes of photos of celebrities in their most intimate and private moments and without a way to verify digital photographs they could be duped of millions of dollars.
There's nothing concerning about digital images in the courtroom.
Ask the photographer, under oath, "is this representative of what you saw?".
If it was, he says so.
It's really the same as with any other evidence that can be tampered with. If someone testifies under oath that it is what it is then there's no difference between a digital image and any (many?) other types of evidence.
Slashdot? Oh, I just read it for the articles.
any image, not just a digital one, can be changed, modified, or completely faked. Yes, digital technology makes it easier, but this is not a new phenomenon. Juries know (and should be told) that any image introduced into evidence might not be real and could have easily been altered by the other side. Depending on who took the image and the chain of possession, weighed against how believable the picture actually is, will determine how much weight the jury gives to a given photograph.
These digital picture verifiers are nice but not the end of the question. A validation from one of these machines is just some more evidence that the picture is real. It's not conclusive and shouldn't be taken as so. In fact, the evidence of validation from one of these machines might not even be allowed into court if they're extremely unreliable. Daubert to the rescue.
Stupid people make stupid things profitable.
We have that interesting problem at work (Insurance Agency, which is half the reason this article caught my eye) -- we need digicams to do photo inspections of property or automobiles. All of our CSR workstations have CompactFlash readers. Half the new digicams out there don't use CF anymore -- which automatically takes them off my shopping list when I need to get new cameras.
I'd also add to your statement that you are an idiot if you buy a camera that doesn't take standard AA (or AAA) batteries. We also have several sets of NI-MH batts and chargers -- I refuse to buy a digicam with propriety batteries. I can't count how much money and aggravation the standard formats of CF and AA NI-MH batts have saved me -- both on a business and personal level.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
When the appropriate function (Personal Function 31) on the EOS-1D Mark II or EOS-1Ds is activated, a code based on the image contents is generated and appended to the image. When the image is viewed, the data verification software determines the code for the image and compares it with the attached code. If the image contents have been manipulated in any way, the codes will not match and the image cannot be verified as the original.
Note to self: run the signing software *after* altering the image. If the image was alrady signed, display it, take screenshot, alter the image, and re-run the signing software.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
By doing an autocorrelation of the image, you can detect parts that have been copied, but the mathematical part is not that easy, particularly if there are uniform noiseless areas (sky).
I can still deal with 1D autocorrelation, but in 2D my maths skills are rusty...
Non-Linux Penguins ?
This is a funny article on why you shouldn't use your digital camera when trying to detect / prove the existance of ghosts. No not like a bad flat screen playing Quake, but like Casper the Friendly.
He seems real serious about it too....
This is just general, but there are many rules about entering photograghs and other documents.
Fight Spammers!
I'm thinking this is for Canon to target the camera at a specific market where legal evidenciary issues come into play: crime scenes, insurance, autopsy, etc. This is likely not to be a feature that will appear for most consumer products.
What it really shows is more about how the professional film camera market is facing realistic competition from digital cameras.
I would love to see the firmware write all photographs to the CompactFlash already encrypted to my public key. Of course, that would mean you'd have to (1) forego viewing the images on the LCD, or (2) require the private key and allow entering some kind of text phrase or biometrical key.
It's not like I engage in some sort of espionage or porn market, but I want to see more publically available data devices support cradle-to-grave security.
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The camera stores information about focus distance, focal length (zoom) and exposure parameters as well as other data in each image (in EXIF format, commonly). Example:
Also, you'd also have to account for the distortion effects that are measurable and reproducible with each camera model. For example, barrel or pincushion distortions compound if you take a shot of an existing picture.