4 ms·

Aren't there tools that can detect photo manipulation?

by everdev 9y ago

NoGravitas 9y ago
You can tell by the pixels and from having seen a few shops in your time.
dsego 9y ago
This is so obvious you don't need tools.
lolc 9y ago
When the resolution of the source material differs or lossy compression was involved, it can be possible to differentiate between the parts. In it's easiest form you subject suspected forgeries to lossy compression and check with a visual diff whether the loss was uniform. Search for "jpeg artifacts forgery" to get an impression. In this case there is no question.
russdill 9y ago
The tools are most effective against people that don't understand what they are doing. It's pretty straightforward to fool such tools if you know what you are doing a especially if you have access to them.
chasing 9y ago
For the photos in the link, eyeballs. The photo manipulation is poorly done and really obvious. (I mean, there's the clouds issue. And then the fact that the moon is in front of trees in the right-hand image, bottom right.)
tabtab 9y ago
Being that an automated process would probably have a rather fixed set of algorithms to detect phoniness, the crook could work around them. A thorough check will probably always involve old-fashioned detective work, often specific to the subject and environment of the photo itself. By the way, in one photo, the clouds appear to go behind the moon. Unless it's the end-of-times, that can't happen.
jadavies 9y ago
Some photo competitions will ask for original RAW images as well as the actual photograph, e.g. for the Natural History Museum Wildlife Photographer of the Year FAQ: What forms of digital adjustments are NOT acceptable? Adding or removing objects (eg animals, animal parts, plants or people) is not permitted. Why do you request the RAW file, original JPEG, original transparency or negative for all categories? To check that any adjustments made to the image comply with our rules. [ http://www.nhm.ac.uk/visit/wpy/competition/adult-competition/faqs.html http://www.nhm.ac.uk/visit/wpy/competition/adult-competition... ]

Aren't there tools that can detect photo manipulation?

NoGravitas 9y ago

You can tell by the pixels and from having seen a few shops in your time.

dsego 9y ago

This is so obvious you don't need tools.

lolc 9y ago

When the resolution of the source material differs or lossy compression was involved, it can be possible to differentiate between the parts. In it's easiest form you subject suspected forgeries to lossy compression and check with a visual diff whether the loss was uniform. Search for "jpeg artifacts forgery" to get an impression. In this case there is no question.

russdill 9y ago

The tools are most effective against people that don't understand what they are doing. It's pretty straightforward to fool such tools if you know what you are doing a especially if you have access to them.

chasing 9y ago

For the photos in the link, eyeballs. The photo manipulation is poorly done and really obvious. (I mean, there's the clouds issue. And then the fact that the moon is in front of trees in the right-hand image, bottom right.)

tabtab 9y ago

Being that an automated process would probably have a rather fixed set of algorithms to detect phoniness, the crook could work around them. A thorough check will probably always involve old-fashioned detective work, often specific to the subject and environment of the photo itself. By the way, in one photo, the clouds appear to go behind the moon. Unless it's the end-of-times, that can't happen.

jadavies 9y ago

Some photo competitions will ask for original RAW images as well as the actual photograph, e.g. for the Natural History Museum Wildlife Photographer of the Year FAQ: What forms of digital adjustments are NOT acceptable? Adding or removing objects (eg animals, animal parts, plants or people) is not permitted. Why do you request the RAW file, original JPEG, original transparency or negative for all categories? To check that any adjustments made to the image comply with our rules. [ http://www.nhm.ac.uk/visit/wpy/competition/adult-competition/faqs.html http://www.nhm.ac.uk/visit/wpy/competition/adult-competition... ]