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Forensic analysis of recent Victoria's Secret photo
- alexkay 17y agoFollow-up: http://www.hackerfactor.com/blog/index.php?/archives/329-The-Secret-is-Out.html http://www.hackerfactor.com/blog/index.php?/archives/329-The...
- jgrahamc 17y agoSee also http://www.jgc.org/blog/2008/07/photoshopped-iranian-missile-launch.html http://www.jgc.org/blog/2008/07/photoshopped-iranian-missile...
- barmstrong 17y agoI don't understand the criticism really. I would expect Victoria's Secret to photoshop pictures.
- NathanKP 17y agoIt isn't about criticism, it is about forensics, using reasoning and computer algorithms to figure out what people did. It is an intellectual challenge, not a criticism.
- RevRal 17y agoExcept for the handbag. That was terrible.
- NathanKP 17y agoVery true.
- zackattack 17y agoWhoooo cares. Too subtle a visual to perceive at first glance
- ghshephard 17y agoSmall Nit - but the use of "Criticism" does not always mean the pejorative: From: http://en.wikipedia.org/wiki/Criticism http://en.wikipedia.org/wiki/Criticism "The word critic comes from the Greek κριτικός (kritikós), "able to discern" , which in turn derives from the word κριτής (krités), meaning a person who offers reasoned judgment or analysis, value judgment, interpretation, or observation . ...
- d_c 17y agoIndeed!
- NathanKP 17y agoVery brilliant, including the followup. This is forensics at its best.
- adriand 17y agoI would love to see an analysis like that of this photo I first posted to my blog (http://socialtech.ca/ade/index.php/2008/03/beware-the-big-bad-black-wolf/ http://socialtech.ca/ade/index.php/2008/03/beware-the-big-ba...) which generated the usual claims of "Photoshop" on Reddit, until I posted the original version, which kicked off many more claims that it was 'shopped (http://www.reddit.com/r/reddit.com/comments/6byul/to_all_the_photo_experts_on_reddit_who_claimed/ http://www.reddit.com/r/reddit.com/comments/6byul/to_all_the...) Even though, to the best of my knowledge, the photo is 100% real.
- NathanKP 17y agoThat is a pretty scary picture, if it is real. ;) I second the motion that this would be great for analysis by an expert. Why don't you try submitting it to him? He might have a contact somewhere on the site.
- ErrantX 17y agoIm willing to bet there is some tampering going on. The body looks nothing much like a wolf - more like a large dog. If you fiddle with the levels in Photoshop that section does look really suspicious (though Im no expert).
- wensing 17y agoSome of the 'experts' in the comment thread claimed that there was no detectable aberrations when messing with levels or what-have-you in PS.
- heyitsnick 17y agoI'm a gambling man (as my profession). I will offer you (3:2) - my $3 to your $2 says this photo is real. Let me know how much you want to bet, I'd accept someone reputable on HN will escrow. Would you trust the author of this article as the arbiter of the wager, using similar techniques as the Victoria's secret photo? [I have no expert knowledge on photos, wolves, or the photographer in question. But I like a good bet, especially in the pursuit of science!)
- davi 17y agoI didn't know what "Error Level Analysis" was. So: 'Error level analysis (ELA) works by intentionally resaving the image at a known error rate, such as 95%, and then computing the difference between the images. If there is virtually no change, then the cell has reached its local minima for error at that quality level. However, if there is a large amount of change, then the pixels are not at their local minima and are effectively “original”.' From http://www.hackerfactor.com/papers/bh-usa-07-krawetz-wp.pdf http://www.hackerfactor.com/papers/bh-usa-07-krawetz-wp.pdf, a lot of interesting stuff in there.
- johnnybgoode 17y agoThe two pictures the author showed after saying, "Here are two photos of the same model" are of two different women. I'm pretty sure about this, because I know who the first woman is. So it appears he did catch them on some things, but he's made at least one mistake himself. Maybe someone else will know if this led to any other mistakes on his part?
- dbz 17y agoThat would be surprising because the woman look very alike. But if you are correct I bet VS was betting that people would think they are the same women. Meh. Doesn't really matter.
- kingkawn 17y agoYou know her know her, like introduce me know her? Also, other than this possible screw up, this one of the most thorough photoshop analyses I've ever read.
- BRadmin 17y agoHe changed the example pic, adding: "[Update 2009-12-27: There was some debate whether the second picture was the same model. I have changed the second example.]"
- baguasquirrel 17y agohttp://en.wikipedia.org/wiki/Principal_component_analysis http://en.wikipedia.org/wiki/Principal_component_analysis When I read that he used PCA to detect that they modified her bust, I really couldn't believe it. That is really impressive. edit: I guess I should add a little background. PCA was used a good bit in computer vision (and data mining in general) when I was in school. You typically don't see it mentioned outside of those contexts.
- nostrademons 17y agoPCA is used a lot in the financial industry. You can guess how it might be useful there...
- teamonkey 17y agoI'm finding it hard to make the jump from the description on the wiki page to how you get something like the 1st Principle Component image he has there. Can anyone explain further?
- dmarshall 17y agoIs it just me, or does anyone else feel like it would have been much more worthwhile to use an example that actually might have been 'tampered' with, and not edited in post-production? Geeks and their VS--wonder what he did with the lingerie catalog...
- grinich 17y agoThis was used as an example in a short lecture about JPEG compression in one of my classes this term. Here are the slides if you're interested. They give a basic overview of perceptual coding and the 2D Discrete Cosine Transform. http://web.mit.edu/6.02/www/currentsemester/handouts/lectures/L24.pdf http://web.mit.edu/6.02/www/currentsemester/handouts/lecture...
- nshah 17y agoHm... If only people could see the pre-process images...
- arithmetic 17y agoThis is enlightening! I'm an amateur photographer who likes to post-process some images (mostly tweaking contrast, brightness and the hues). This post taught me quite a bit on photography forensics.
- tetha 17y agoBesides the very interesting analysis, is anyone besides me disturbed by her face in the various analysis images? It looks really, really disturbing in some pictures.
- xcombinator 17y agoI love the article, and the Sherlock Holmes analysis too: -Ohh, let me see... a professional photo could be manipulated by Photoshop or Gimp... -mmmmm. It's photoshop what had been used. He is truly a genius!!
- tvon 17y agoIf the "ELA" indicates edited regions, why is the region where the most obvious change happened (the bag) one of the darkest? I'm also not convinced on the lightening of the skin tone. The lighting is entirely different in both pictures, and I have friends who have shifted tone more than that after a summer of tanning. (edit: her hair is much darker as well)