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Wednesday, October 10, 2012

FourMatch in an Image Authentication Workflow

Four and Six recently posted the latest in a series of blog posts placing their new FourMatch authentication tool in context within the larger image authentication workflow.

" ... The biggest strength of FourMatch is its ability to provide compelling evidence that an image file has not been modified since it was first captured. However, FourMatch is not designed to tell you whether an image is untruthful. It merely tells you whether the photo remains in the pristine state it would be in coming direct from the camera. That means that many files that fail the FourMatch test may still be truthful images. Perhaps someone just cropped the image without altering the remaining photo content. Or perhaps someone just re-saved the photo using a higher degree of JPEG compression in order to make the file smaller to upload to the Internet. Both of these changes would cause the resulting file to fail the FourMatch test, even though the actual content of the file is still reliable ..."

" ... Let’s start with considering FourMatch as a standalone authentication measure. Particularly within a legal setting, there are many times when people may need assurance that an image can be trusted, particularly given the ease with which images can be manipulated with modern software ..." Two things come to mind, is it possible that an image is authentic, completely untouched by software, yet fail the test? Meet the black swan. Even though their database is quite robust, it still needs updating regularly. Thus, the software - given the tremendous head start - will play catch up as new phones and cameras come out. Not finding that black swan depends on keeping your subscription up to date, keeping your local database up to date, and Four and Six keeping their end up to date. Also, as it's software and it's database driven, can it be spoofed? Hmmm.

At this point, I think it's abundantly clear what FourMatch is and isn't. The question now is ... is it worth the initial price + on-going subscription (+ off-line surcharge for those folks who have an un-internet-connected lab) for what it provides? Given that a lot of folks haven't upgraded from Photoshop CS3, this cost also includes upgrading Photoshop as well.

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