Muzzlehatch PRO 8:13pm, 6 October 2010
I found this here website that purports to digitally examine photographs and report whether or not they have been "altered."

errorlevelanalysis.com

You provide the site a link to a jpeg, hit "process," and seconds later it shows you a goofy side by side comparison that may (or may not) show where a photograph has been manipulated.

From the FAQ:

Error level analysis allows you see to see the difference in quality level, represented by brightness. Things which are very bright have been edited most recently, whilst duller parts have been resaved multiple times. This allows you to see not just which parts of the image have been changed, but in what order the changes occurred.


It shows all my pics have been manipulated, but not really in the right places. I chalk it up to flickr's compression algorithms. Of course, you can also use the site to impress your mom and/or win bar bets.

Anyhow, the site captivated me for a couple of minutes and I thought I'd share.
The Blue Boy 5 years ago
Cheers Mr Hatch!
Muzzlehatch PRO 5 years ago
Did you win a bar bet yet?
Eli the Bearded 5 years ago
I really like the way it manipulated one of my images:

errorlevelanalysis.com/permalink/460978b/

(The original is part of a series showing image corruption after many small rotates.)
uaka-uaka 5 years ago
interesting! I'll try!
monaxle 5 years ago
captivated me for a couple of minutes too.
Woof. Posted 5 years ago. Edited by Woof. (member) 5 years ago
how's that going to work with an image that's been processed as a NEF (RAW file) in software like Capture NX2 before being saved to JPG?

Every single alteration made by NX2 (when working on a NEF file) is made right from scratch, ie. the whole file is reworked each time.

It gets saved to JPG once, then mashed by Flickr when it's uploaded, equally, all over.

Oh hang on, I keep forgetting, in the photo world, everyone uses Photoshop or they don't exist... silly me

edit: not criticising you, Muzz, btw
Muzzlehatch PRO 5 years ago
Same here... I shoot raw and only save the photo to jpeg once.

But, If I were to grab something off the internet and paste it into my picture, for instance (say, a picture of Julianne Moore laying next to me, having my baby), then the pasted in elements will be of a differing quality and that would show.

I'm sure there are other applications as well. For our photos, which are saved only once in their entirety, recompressed in their entirety by flickr, etc, it wouldn't be as helpful.
"Mike Foster" PRO 5 years ago
Why would anyone want to lie next to someone having their baby? The noise would be dreadful.
Muzzlehatch PRO 5 years ago
But soooo worth it. 10 years ago.
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