On 07/07/2017 04:17 PM, Ryan Carboni wrote:
Patent 9,525,866, from 2016, is anti-camera forensics. Time to go back to film! (or maybe just resize it to 50% and save it as a rather lossy JPEG)
I would not trust that very far: Signatures from hot pixels may remain visible to the naked eye as well as statistical analysis, and variations in color registration across larger areas of the sensor would survive. A camera signature does not need to be unique to be very valuable to an adversary who has other means at hand to narrow the field of candidates for creator of this or that image of interest. Conversion to a vector format with the aid of an auto-trace program should work reliably, at the cost of a /massive/ loss of resolution. If the photo needs to still look like a photo when you're done sanitizing it, the GMIC filter pack's tool set may be useful, with effects like bilateral smoothing etc. that wipe out small scale noise signatures. Conversion to grayscale, or or reducing color resolution and changing RGB balance would also be a good idea. Exporting sanitized images in an indexed format with a limited size palette (i.e. GIF) would be helpful. But no matter what, if you remove enough detail to confidently disassociate the photo from the camera, image quality will suffer quite visibly. One's method for altering photos to disassociate them from individual camera sensors would have to change often or it would create a trail of its own. :o)