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New Service Converts Torrents Into PNG Images
jamie points out that a new web service, hid.im, will encode a torrent into a PNG image file, allowing it to be shared easily through forums or image hosting sites. Quoting TorrentFreak:
"We have to admit that the usefulness of the service escaped us when we first discovered the project. So, we contacted Michael Nutt, one of the people running the project to find out what it's all about. 'It is an attempt to make torrents more resilient,' Michael told [us]. 'The difference is that you no longer need an indexing site to host your torrent file. Many forums will allow uploading images but not other types of files.' Hiding a torrent file inside an image is easy enough. Just select a torrent file stored on your local hard drive and Hid.im will take care the rest. The only limit to the service is that the size of the torrent file cannot exceed 250KB. ... People on the receiving end can decode the images and get the original .torrent file through a Firefox extension or bookmarklet. The code is entirely open source and Michael Nutt told us that they are hoping for people to contribute to it by creating additional decoders supported by other browsers."
Here's an example. It's the OpenOffice.org 3.1.0 win32 torrent taken from the OO.o site.
Say, MIME ...?
I think you mean base64.
As for hiding it, I think that's sort of the point behind this scheme.
TPB was purchased by a gaming company and has gone legitimate.
Gentlemen! You can't fight in here, this is the war room!
I don't get why they can't just use the old trick of hiding a zip file in an image file.
Seems simpler, technology-wise, to me than encoding a torrent file as a PNG image, and all you would have to do to get the torrent file is change the extension on the file. Also seems safer. Unless this trick wouldn't be possible with .torrent files, that is?
I'm half tempted to pop it open myself and add a feature that inserts a text description into the encoded PNG. Really, I don't think it would be too hard (hell, it could just have a few flag bits that tell the interpreter how much of the image needs to be cropped to remove the description.)
"Sorrow is better than laughter, for by sadness of face the heart is made glad." [Ecclesiastes 7:3]
Instead, what they're doing here is encoding the data contained in a torrent file as valid image data. I'm not sure exactly what technique they're using, but the process is essentially analogous (though surely more complex) to treating each bit as a black/white pixel indicator. Given some agreed upon dimensions for the image (either width or height, doesn't matter which) this gives you a black and white bitmap which could then be encoded as a png.
Clearly what they are doing is more complex since their images are color (and they may be relying on specifics of the way png images are formatted), but the basic idea is the same.
This is for encoding the .torrent file. Not whatever it points to.
For example, I just found a torrent file for Terminator Salvation - 14kB
Filename extensions are a form of metadata, and I don't think it sets a good precedent to lie in the metadata for a file. It's bad enough that we have Windows hiding filename extensions from the user, and encouraging people to just double-click on a file to launch the associated app. This just seems like asking for more problems, as people try to double-click on mjthriller.png and it launches - and crashes - IE.
I know, I know... This is Slashdot, nobody reads the article. But could you at least read the summary?
They aren't re-naming a file. They aren't just dropping the .torrent extension and replacing it with .png The resulting file isn't going to run any malicious code or do anything bizzarre.
They're encoding the bits of the .torrent file in a .png image. It actually creates an image. Looks like some kind of abstract/modern art kind of thing... Blocks of bright colors. You could open it with any graphics program... Set it as your wallpaper... Send it off to WalMart to be printed on photo paper...
"Work is the curse of the drinking classes." -Oscar Wilde
I built a utility that can be used for the same purpose back in april. http://cosmodro.me/blog/2009/apr/11/smuggle-improved/
It's a small flash movie that can encode files into pngs and decode them back. It's not limited to torrents, so you can encode any file that's less than about 16MB.
------- Driver carries less than 64K of cache.
PNG could also place torrent data in non-image file chunks which regular viewers would ignore. That's the method I was expecting, but it doesn't look that way from the screenshots.
Ita erat quando hic adveni.