ProofMode: a camera app for verifiable photography

Posted Jun 26, 2017 5:34 UTC (Mon) by mjthayer (guest, #39183)
In reply to: ProofMode: a camera app for verifiable photography by droundy
Parent article: ProofMode: a camera app for verifiable photography

To my mind the main proof that a picture is not faked would be sharing the hash of the image too close to the time of the event in question for there to have been time to fake it. (As long as we have not reached the point where "Siri, fake that picture" is feasible. Who knows then that will be.) I don't see much value in the location data and so on either. It seems to me that if the algorithm is known and there is time to fake anything at all then there will be time to fake the meta data.

ProofMode: a camera app for verifiable photography

Posted Jun 26, 2017 7:59 UTC (Mon) by hifi (guest, #109741) [Link]

I think it works only to prove that you are the author of an image by providing the hash as early as you can. A neutral third party site that you can upload a hash of the raw/source image can be proof of ownership. Whoever uploaded the hash first owns the picture. The site doesn't need to store anything else than the hash, uploader and the upload time for verification purposes. Whatever the image metadata itself says about the time and place isn't verifiable.

This could help fight against *other* people doctoring your image and claiming it to be the original as you can always prove that the original image file you have had been hashed before the fake image proving you have the original.

I don't see any way to unanimously prove when/where a picture was taken, only the earliest time when it was publicly known to exist and who claimed to own it at that time.