Several years back, science-fiction author William Gibson released a book on disc that self-destructed after one read. A quick google shows that the book was “Agrippa”. Not sure of the details, and like others have said, taking a screen shot could easily defeat it, but it might be worth checking out just to see how he did it.
There was just such an item on a Law and Order Criminal Intent episode I saw last night, so it MUST be possible.
What?
Interesting. LCD shutters in the goggles, I expect. Same technology has been used to make 3-D goggles, by alternatively blocking the right and left eye.
Although it will only protect the document from bystanders. It won’t protect the document from the recipient himself - all he needs to do is photograph the screen through the goggles. (Unless you incorporate biometric sensors into the goggles… Hmm, a retinal scanner would be a natural choice…)
Elaboration on the webserver idea.
How about using a PHP script or Perl cgi to serve the image when presented with the correct password.
After serving the image the script overwrites the image file on the server with something else (e.g. a black fill).
The script also performs a browser refresh after a set period, say 30 seconds, thus clearing the browser cache.
And the experiment failed, at least to the extent “Agrippa” is available online if you know where to look. In fact, the scheme was cracked fairly quickly and the full text was available to download when the book was still pretty new.
How about rendering the image as a vector graphic, but generated by a program that’s such a grotesque hog of resources that you can barely even run it, and that’d crash if you tried to take a screenshot?
How do you know about Adobe Illustrator?
PHP or Perl would both be ways to do it. I know JSP’s / servlets, and would probably set this up on a J2EE server because I have one handy.
How you would manage copies of the image, and how they are addressed via server requests is an implementation detail. It is indeed very likely that you would make and erase a uniquely named copy for each request.
I assume you mean that the delivered content has a metarefresh which would cause the thing to redisplay after a timeout. Yeah, if you want to limit the amount of time they are allowed to look at it, it might be reasonable. Does diddly if they simply shut the browser before refresh. You still want to put all the various “do not cache” directions honored by the various browsers in your delivered page, and not show them a cacheable .jpg in the content. Does anybody know if javascripting a load of an IMG tag causes the image fetched in the javascript to be cached by the browser?
By the time you get to things like making custom goggles, though, it’d be much easier to just hand the other person a photo printed on something which will chemically degrade quickly, or better yet, to keep ahold of the photo in your hand while you show it to them in person. Or, as I suspect may be the case here, show them the scene in question in person, without ever photographing it.
Could you deliver the message by airplane skywriter? The message would gradually degrade.
http://www.skywriter.info/
I wouldn’t say that it failed. As I remember it, he expected it to be cracked; the challenge was part of the artwork. (No cite; I believe I read it in Mondo 2000 magazine.)
One of the places that one may find it is William Gibson’s official website: http://www.williamgibsonbooks.com/source/agrippa.asp
Mission: Impossible was waaaay ahead of them.
Trivially defeated by curl or wget.
I believe the question was answered by the very first reply.
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Kind of a tangent, but there used to be such things as watch-once videotapes - they contained a magnet in the take-up mechanism - so that the information on the tape was destroyed after it had passed the tape reading head. I can’t remember why they were used.
And of course these can be defeated by removing the magnet, if you realise it’s there before watching the tape.