- Messages
- 6,671
- Name
- Wail
- Edit My Images
- No
Like this Nikon application, is there such a program that can help me identify if a picture is altered that works on most, if not all, brands & models?
Image Authentication application, for all camera brands / models ...
- Thread starter Wail
- Start date
- Messages
- 11,513
- Name
- Stewart
- Edit My Images
- Yes
Interesting question... but I strongly suspect the answer is no.
The only way for an application like this to work is for the camera to compute some sort of checksum or fingerprint based on the content of the image file, and add it to the image file in the EXIF data. Then the software application will compute the same function and see whether it matches. But the function itself HAS to be proprietary and not amenable to reverse engineering; otherwise there may be ways to circumvent it. Plus, the sofrware application which confirms the authenticity of the image has to be above reproach itself... which is why they cost so much!
The only way for an application like this to work is for the camera to compute some sort of checksum or fingerprint based on the content of the image file, and add it to the image file in the EXIF data. Then the software application will compute the same function and see whether it matches. But the function itself HAS to be proprietary and not amenable to reverse engineering; otherwise there may be ways to circumvent it. Plus, the sofrware application which confirms the authenticity of the image has to be above reproach itself... which is why they cost so much!
OP
- Messages
- 6,671
- Name
- Wail
- Edit My Images
- No
Stewart,
Thank you for the detailed reply
Can I ask, then, how do competitions that specify no adjustments to photos make sure that a submission has not been altered in any way?
Nikon resolves this with their application, but world competition & photo libraries get submissions from all brands!?
Thank you for the detailed reply
Can I ask, then, how do competitions that specify no adjustments to photos make sure that a submission has not been altered in any way?
Nikon resolves this with their application, but world competition & photo libraries get submissions from all brands!?
- Messages
- 11,513
- Name
- Stewart
- Edit My Images
- Yes
I would imagine that, for the most part, they can't make 100% sure.
Requiring entrants to submit the original negative / transparency / RAW file would allow them to check the print / entry against the original capture. That would suffice to identify most alterations, and if entrants know that this was a condition of entry then it would surely act as a deterrent against alteration.
It wouldn't catch the really dedicated cheat, but that's not the point.
The Nikon authentication software costs £500+, and the Canon equivalent is even more expensive. I would imagine the primary market for these tools is law enforcement, where you really do want to be 100% sure that the photo hasn't been tampered with.
OP
- Messages
- 6,671
- Name
- Wail
- Edit My Images
- No
Again, thank you
I didn't know Canon had such an application.
On the RAW issue; how can I tell if a file has been altered after being shot? I ask, since I always shoot RAW yet when I import my shots in to Lightroom it always says Metadata has been altered, even though I haven't changed a thing :shrug:!
I didn't know Canon had such an application.
On the RAW issue; how can I tell if a file has been altered after being shot? I ask, since I always shoot RAW yet when I import my shots in to Lightroom it always says Metadata has been altered, even though I haven't changed a thing :shrug:!
- Messages
- 11,513
- Name
- Stewart
- Edit My Images
- Yes
No idea. It's probably something to do with the way you have the import facility configured in Lightroom, but I don't know anywhere near enough about Lightroom to suggest what.
Remember though, that as far as Lightroom is concerned, metadata isn't all in the RAW file. Some of it is, but Lightroom also creates a .xmp file for each image, where it stores additional metadata.
Changing a RAW file isn't trivial. Most image editors don't even try. I know that it's possible to change the EXIF capture time in the RAW file, which can be handy if you travel abroad and forget to set the camera's clock to the new time zone. BreezeBrowser is an application that allows that, though there may be others. But I'm not aware of any means to do anything else of significance to a RAW file.
OP
- Messages
- 6,671
- Name
- Wail
- Edit My Images
- No
In the Library module, under Metadata, I get: -
[Metadata Status Has been changed]
That's what I see after importing my images.
On import, I do nothing that I'm aware of to my image that would cause this! I will have a look more closely next time I import some pictures.
Back to image authentication; what I understand is basically, the best means to ascertain images have not been adjusted / manipulated is to use the applications by the respective manufacturer.
Thanks
[Metadata Status Has been changed]
That's what I see after importing my images.
On import, I do nothing that I'm aware of to my image that would cause this! I will have a look more closely next time I import some pictures.
Back to image authentication; what I understand is basically, the best means to ascertain images have not been adjusted / manipulated is to use the applications by the respective manufacturer.
Thanks