Comments on: Untwirling photo of a suspected pedophile http://boingboing.net/2007/10/08/untwirling-photo-of.html Brain candy for Happy Mutants Sun, 19 May 2013 01:09:00 +0000 hourly 1 http://wordpress.org/?v=3.4.1 By: DragonPhyre http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42500 DragonPhyre Wed, 30 Nov -0001 00:00:00 +0000 #comment-42500 Checking now... Yes. This is possible. Simply run the filter back with negative values and it comes right back. This is also possible in The Gimp, a freely avialable tool that you can download and use without paying a dime for Photochop. Checking now… Yes. This is possible. Simply run the filter back with negative values and it comes right back.

This is also possible in The Gimp, a freely avialable tool that you can download and use without paying a dime for Photochop.

]]> By: Cpt. Tim http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42508 Cpt. Tim Wed, 30 Nov -0001 00:00:00 +0000 #comment-42508 "Checking now... Yes. This is possible. Simply run the filter back with negative values and it comes right back." yep. i learned this playing around with my first photo editing program in the 90's when just playing with twirl filters was almost as fun as a video game. “Checking now… Yes. This is possible. Simply run the filter back with negative values and it comes right back.”

yep. i learned this playing around with my first photo editing program in the 90′s when just playing with twirl filters was almost as fun as a video game.

]]> By: cristiancontini http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-43021 cristiancontini Wed, 30 Nov -0001 00:00:00 +0000 #comment-43021 Yes sure, photoshop work perfectly..for mac user there is also a "photo rebooth" for Photo Booth http://tinyurl.com/3xp9p3 Yes sure, photoshop work perfectly..for mac user there is also a “photo rebooth” for Photo Booth

http://tinyurl.com/3xp9p3

]]> By: Christovir http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42515 Christovir Wed, 30 Nov -0001 00:00:00 +0000 #comment-42515 This is the technological equivalent of putting a jpg in a zip file and renaming the extension, and then classifying the reversal process. I'm reminded of a police release I read about growing opium poppies, saying they were so difficult to cultivate that it would be impossible for most phds to do so if they tried. Of course, poppies are largely self-seeding, and most of the world's supply is grown by millions of illiterate farmers throughout Asia. This is the technological equivalent of putting a jpg in a zip file and renaming the extension, and then classifying the reversal process.

I’m reminded of a police release I read about growing opium poppies, saying they were so difficult to cultivate that it would be impossible for most phds to do so if they tried. Of course, poppies are largely self-seeding, and most of the world’s supply is grown by millions of illiterate farmers throughout Asia.

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42522 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42522 "Do they think that molesters will keep doing this now that it can be reversed, if they don't know HOW it's being reversed? WTF" Criminals are dumb plain and simple. A lot of them still believe the old urban legend that an undercover police officer has to stop being undercover if asked "are you a cop?". Molesters often form networks comprised of guess what molesters who share tips on how to avoid police, where to go to snatch kids who won't talk, how to avoid having their images of child porn not be found on the computers they take in to be repaired. So if a false method of avoiding police becomes standard among these molesters then they will for example post phots of themselves abusing children on the web in very public areas that will certainty be found out about by the police. The police will then easily reverse the image allowing them to identify and thereby more easily track down the molester. Since the molesters wouldn't know that was how they were found out they would continue to use the technique thinking they wouldn't be caught. “Do they think that molesters will keep doing this now that it can be reversed, if they don’t know HOW it’s being reversed? WTF”

Criminals are dumb plain and simple. A lot of them still believe the old urban legend that an undercover police officer has to stop being undercover if asked “are you a cop?”.

Molesters often form networks comprised of guess what molesters who share tips on how to avoid police, where to go to snatch kids who won’t talk, how to avoid having their images of child porn not be found on the computers they take in to be repaired. So if a false method of avoiding police becomes standard among these molesters then they will for example post phots of themselves abusing children on the web in very public areas that will certainty be found out about by the police. The police will then easily reverse the image allowing them to identify and thereby more easily track down the molester. Since the molesters wouldn’t know that was how they were found out they would continue to use the technique thinking they wouldn’t be caught.

]]> By: mellowknees http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42524 mellowknees Wed, 30 Nov -0001 00:00:00 +0000 #comment-42524 Though it's not a huge secret how to untwirl a photo like this...there are valid reasons for not shouting from the moutaintops how they did it. Here's a snippet from the news story about this: "Tipping criminals off to the techniques that police have at their disposal could also prompt them to better hide their identities." Though it’s not a huge secret how to untwirl a photo like this…there are valid reasons for not shouting from the moutaintops how they did it. Here’s a snippet from the news story about this:

“Tipping criminals off to the techniques that police have at their disposal could also prompt them to better hide their identities.”

]]> By: Cpt. Tim http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42530 Cpt. Tim Wed, 30 Nov -0001 00:00:00 +0000 #comment-42530 you mean like simply cutting the face out entirely? face it, this was a freebie, if it happens again it will be because a criminal didn't see this story at ALL, not because he didn't know about their de-swirling techniques. you mean like simply cutting the face out entirely?

face it, this was a freebie, if it happens again it will be because a criminal didn’t see this story at ALL, not because he didn’t know about their de-swirling techniques.

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42534 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42534 It's like a laminar flow effect :) http://www.youtube.com/watch?v=p08_KlTKP50 seriously, some info can be retrieved from non updated thumbnails and EXIF data, after editing, and some warp effects are reversible, even the "randomness" is sometimes calculable. Nothing like and old and trusty solid black block of privacy, and a program like jpgclean to remove any embedded metadata. Fred the Anonymous It’s like a laminar flow effect :)

http://www.youtube.com/watch?v=p08_KlTKP50

seriously, some info can be retrieved from
non updated thumbnails and EXIF data, after
editing, and some warp effects are reversible,
even the “randomness” is sometimes calculable.

Nothing like and old and trusty solid black block
of privacy, and a program like jpgclean to
remove any embedded metadata.

Fred the Anonymous

]]> By: Humptydank http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-43310 Humptydank Wed, 30 Nov -0001 00:00:00 +0000 #comment-43310 Before everyone goes condemning this guy, keep in mind that the camera adds ten boys. Before everyone goes condemning this guy, keep in mind that the camera adds ten boys.

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42548 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42548 A slightly more sophisticated technique is used in the pixelization of genitalia on some Japanese porn, primarily online hentai manga. Blocks of the image have mosaics pixelization applied with a password, the same password can later be used to reverse the mosaic. it is a huuuuuge secret, the lore of the otaku. A slightly more sophisticated technique is used in the pixelization of genitalia on some Japanese porn, primarily online hentai manga.

Blocks of the image have mosaics pixelization applied with a password, the same password can later be used to reverse the mosaic.

it is a huuuuuge secret, the lore of the otaku.

]]> By: Elvis Gump http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42560 Elvis Gump Wed, 30 Nov -0001 00:00:00 +0000 #comment-42560 Twirling/untwirling is some stupid pixel trick I remember seeing at least a decade ago on some how to site, maybe even one of those Adobe tutorials. Twirling/untwirling is some stupid pixel trick I remember seeing at least a decade ago on some how to site, maybe even one of those Adobe tutorials.

]]> By: nex http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-43076 nex Wed, 30 Nov -0001 00:00:00 +0000 #comment-43076 You can undo everything to the extent that it just re-arranged information, as opposed to throwing information away. You just need to know the transformation function or be able to guess an approximation that is close enough. E.g. encrypting a file preserves all of the information perfectly, but you need the key to undo it (even for ROT13, but there the key is easily guessed.) Under these criteria, using standard Photoshop twirl is pretty much the stupidest thing you can do. You can undo everything to the extent that it just re-arranged information, as opposed to throwing information away. You just need to know the transformation function or be able to guess an approximation that is close enough. E.g. encrypting a file preserves all of the information perfectly, but you need the key to undo it (even for ROT13, but there the key is easily guessed.) Under these criteria, using standard Photoshop twirl is pretty much the stupidest thing you can do.

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42571 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42571 This twirling as concealment is in fact just a graphical equivalent of very bad crypto. The plaintext is the original image. This is just a series of numbers. The guy then applied a widely known mathematical algorithm to that a set of numbers to obtain the "concealtext". Problem is that anyone that knows the algorithm can obtain the original image (or a close enough one given that there are some variables) without much ado. This twirling as concealment is in fact just a graphical equivalent of very bad crypto. The plaintext is the original image. This is just a series of numbers. The guy then applied a widely known mathematical algorithm to that a set of numbers to obtain the “concealtext”. Problem is that anyone that knows the algorithm can obtain the original image (or a close enough one given that there are some variables) without much ado.

]]> By: Mark Jaquith http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42601 Mark Jaquith Wed, 30 Nov -0001 00:00:00 +0000 #comment-42601 Techniques such as twirling or blurring or pixelating are not foolproof methods of visual obfuscation. If you want to hide information, you should obscure it completely. Techniques such as twirling or blurring or pixelating are not foolproof methods of visual obfuscation. If you want to hide information, you should obscure it completely.

]]> By: stuart kaufman http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42608 stuart kaufman Wed, 30 Nov -0001 00:00:00 +0000 #comment-42608 This story appeared last night on 60 Minutes. See "The Man from Interpol" at http://www.cbsnews.com/sections/60minutes/main3415.shtml This story appeared last night on 60 Minutes. See “The Man from Interpol” at
http://www.cbsnews.com/sections/60minutes/main3415.shtml

]]> By: mellowknees http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42611 mellowknees Wed, 30 Nov -0001 00:00:00 +0000 #comment-42611 "#17 posted by Cpt. Tim , October 8, 2007 2:26 PM: you mean like simply cutting the face out entirely? face it, this was a freebie, if it happens again it will be because a criminal didn't see this story at ALL, not because he didn't know about their de-swirling techniques." Oh no, I totally agree with you. If he actually thought that being swirled would protect him from getting caught, he's an idiot. Well, clearly he's an idiot to begin with. I think that the cops are just hoping that other pedophiles will be just as stupid, and they're worried that by pointing out how dumb this is, they'll do something "smarter" to obscure their identities. But honestly, if they're this stupid to begin with, how genius could any of their new ideas be? “#17 posted by Cpt. Tim , October 8, 2007 2:26 PM:
you mean like simply cutting the face out entirely?

face it, this was a freebie, if it happens again it will be because a criminal didn’t see this story at ALL, not because he didn’t know about their de-swirling techniques.”

Oh no, I totally agree with you. If he actually thought that being swirled would protect him from getting caught, he’s an idiot. Well, clearly he’s an idiot to begin with.

I think that the cops are just hoping that other pedophiles will be just as stupid, and they’re worried that by pointing out how dumb this is, they’ll do something “smarter” to obscure their identities. But honestly, if they’re this stupid to begin with, how genius could any of their new ideas be?

]]> By: knodi http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42867 knodi Wed, 30 Nov -0001 00:00:00 +0000 #comment-42867 <em>"Forget Photoshop - I'd like to tattoo a permanent red bullseye on this creep's forehead."</em> Oh no! India's full of child molesters! “Forget Photoshop – I’d like to tattoo a permanent red bullseye on this creep’s forehead.”

Oh no! India’s full of child molesters!

]]> By: yurei http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42637 yurei Wed, 30 Nov -0001 00:00:00 +0000 #comment-42637 Forget Photoshop - I'd like to tattoo a permanent red bullseye on this creep's forehead. Forget Photoshop – I’d like to tattoo a permanent red bullseye on this creep’s forehead.

]]> By: OM http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42923 OM Wed, 30 Nov -0001 00:00:00 +0000 #comment-42923 ...Actually, all these scumbags need to do to defeat the "anti-twirl" is to use at least two more distort filters after the twirl that do *not* have a reversible direction. In this case, using Radial Blur in Zoom mode after running a Mosaic would totally frack the face where it couldn't be restructured. On the other hand, if the bastard had simply put a big black blot over his entire head, that would have been just as effective. Now, if only there was an automatic death penalty for pedophiles, this would be a non-issue... …Actually, all these scumbags need to do to defeat the “anti-twirl” is to use at least two more distort filters after the twirl that do *not* have a reversible direction. In this case, using Radial Blur in Zoom mode after running a Mosaic would totally frack the face where it couldn’t be restructured. On the other hand, if the bastard had simply put a big black blot over his entire head, that would have been just as effective.

Now, if only there was an automatic death penalty for pedophiles, this would be a non-issue…

]]> By: Photoshop User http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-673465 Photoshop User Wed, 30 Nov -0001 00:00:00 +0000 #comment-673465 Ok, here's what I've noticed. when trying it with my own test pictures. It is NOT is simple to undo it as you might think. There are several factors: Shape of selection tool (circle, square, oval, rectangle) Size of selection Center of selection If any one of these is off by just ONE PIXEL, the ability to un twirl it is greatly compromised. If off by 2 or more pixels, you might as well just forget it, as it looks just as distorted as (but distorted in a different way) as when the picture started. To overcome this, you'd either have to be VERY LUCKY, be SUPER observant as to EXACLY how the twirl looked and guess VERY accuratly as to the specs used to generate the twirl, or you'd have to have a computer analyze the picture with an algorithm written by a PHD in computer science to determine the EXACT specifications of the twirl used. I tend to think it is the last of these possibilities. Someone probably wrote advanced "twirl analizing" software, and it is that software that the police are keeping secret, VERY SECRET. Ok, here’s what I’ve noticed. when trying it with my own test pictures. It is NOT is simple to undo it as you might think. There are several factors:

Shape of selection tool (circle, square, oval, rectangle)
Size of selection
Center of selection

If any one of these is off by just ONE PIXEL, the ability to un twirl it is greatly compromised. If off by 2 or more pixels, you might as well just forget it, as it looks just as distorted as (but distorted in a different way) as when the picture started.

To overcome this, you’d either have to be VERY LUCKY, be SUPER observant as to EXACLY how the twirl looked and guess VERY accuratly as to the specs used to generate the twirl, or you’d have to have a computer analyze the picture with an algorithm written by a PHD in computer science to determine the EXACT specifications of the twirl used. I tend to think it is the last of these possibilities. Someone probably wrote advanced “twirl analizing” software, and it is that software that the police are keeping secret, VERY SECRET.

]]> By: poosnews http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42692 poosnews Wed, 30 Nov -0001 00:00:00 +0000 #comment-42692 This weirdo must want to get caught. You can't underestimate anything in today's world, especially after it was announced that the first synthetic chromosome has been successfully created. This weirdo must want to get caught. You can’t underestimate anything in today’s world, especially after it was announced that the first synthetic chromosome has been successfully created.

]]> By: Cpt. Tim http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42447 Cpt. Tim Wed, 30 Nov -0001 00:00:00 +0000 #comment-42447 "a capability that at least one Interpol official was intent on keeping confidential." cause its a huuuuuge secret. “a capability that at least one Interpol official was intent on keeping confidential.”

cause its a huuuuuge secret.

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42451 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42451 So... wouldn't the confidential method simply to use Photoshop to twirl in the opposite direction? So… wouldn’t the confidential method simply to use Photoshop to twirl in the opposite direction?

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-502996 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-502996 twas like man to leave a trail a tale for a poet who happened to know it when the prabability narrowed and she left ink lying foreign and NEILA 1 4 2 and where r you twas like man to leave
a trail

a tale for a poet
who happened to know it

when the prabability narrowed
and she left ink lying

foreign and NEILA
1 4 2
and where r you

]]> By: x http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42453 x Wed, 30 Nov -0001 00:00:00 +0000 #comment-42453 Yet another great example of a photoshop nerd saving the world from evil! Yet another great example of a photoshop nerd saving the world from evil!

]]> By: Tgg161 http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42455 Tgg161 Wed, 30 Nov -0001 00:00:00 +0000 #comment-42455 Presumably, the 'top secret' method would be setting Photoshop's twirl tool to a negative number. (though it wouldn't work with the small/compressed version provided here) Presumably, the ‘top secret’ method would be setting Photoshop’s twirl tool to a negative number.

(though it wouldn’t work with the small/compressed version provided here)

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42456 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42456 Twirling in the opposite direction, eh? Crack team of Photoshop experts these interpol officials are. Twirling in the opposite direction, eh? Crack team of Photoshop experts these interpol officials are.

]]> By: Dave X http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42460 Dave X Wed, 30 Nov -0001 00:00:00 +0000 #comment-42460 Ask Interpol if they have any "thumb-removal" plugins for me, eh? Ask Interpol if they have any “thumb-removal” plugins for me, eh?

]]> By: Anonymous http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42463 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-42463 Actually there are several different ways of un-twirling. While Photoshops' "negative value" twirl will give some result, Matlab can be used to un-twirl and in some cases even un-blur images that have been otherwise manipulated. There are several documented algorithms that can be used to distort and un-distort images. The problem is pixels. Reverse-gaussian transforms can be applied and such, but if the pixel data is destroyed, you can't just recover it. Only interpolate what's still there. Actually there are several different ways of un-twirling. While Photoshops’ “negative value” twirl will give some result, Matlab can be used to un-twirl and in some cases even un-blur images that have been otherwise manipulated. There are several documented algorithms that can be used to distort and un-distort images.

The problem is pixels. Reverse-gaussian transforms can be applied and such, but if the pixel data is destroyed, you can’t just recover it. Only interpolate what’s still there.

]]> By: dculberson http://boingboing.net/2007/10/08/untwirling-photo-of.html#comment-42469 dculberson Wed, 30 Nov -0001 00:00:00 +0000 #comment-42469 Nobody's said it, so I have to: that dude has one hell of a child molester stare going on. Nobody’s said it, so I have to: that dude has one hell of a child molester stare going on.

]]>