Short answer: you can't.

Unless you have total control over the end-user's computer, it can't be done. As long as they can access it, be it to view or to print, they can copy it. You may be able to make it difficult or annoying to do so but it will always be possible.

Consider: To print the data, they have to copy it from memory to the printer. What would stop them from intercepting the data there, possibly even with specialized hardware? I know this is extreme and almost no one would do it but my point is that they could.

And there are many, many ways that are much easier whereby they could copy the data that you could not stop without standing over their shoulder as long as they view it (or longer).

If you (and your boss) would settle for merely making it difficult, then you should perhaps ask yourself: Why? Why are these people that you are allowing access to your precious data not trustworthy enough in your eyes that they would copy your data? Perhaps they should not be given access in the first place. Or perhaps you should not be so paranoid about people copying your data.

Of course, it's entirely possible that I'm just confused. ;-)

Addendum: If by "browser" you mean web browser, then even making it difficult is nigh unto impossible. They could always wget(1)... (Unless, of course, you're talking about Windoze Lusers... ;-)

bbfu
Seasons don't fear The Reaper.
Nor do the wind, the sun, and the rain.
We can be like they are.

Also,
It's very easy for someone to do a screen capture of the browser window. (make an image of it)

- p u n k k i d
"Reality is merely an illusion, albeit a very persistent one." -Albert Einstein

Take a look at http://www.iengineer.com/. This company specializes in the read-only display of about five different well known CAD formats. They have licenses to render each one, then they publish to a public plugin the user gets. Even better, ienginner will do change management, archive, collaborative tools and write and read-only, but annoteable (is that a word?) formats. Cool and no coding. They are also good enginners in CAD and know their (*^%*&^. I don't work for them, but I have met their team.

-diskcrash

Good Luck.

You can try tricky stuff with JavaScript to prevent the right mouse button submenu from allowing "image save". But then they only need to turn off JavaScript.

As mentioned previously, either dump the paranoia or get much more proactive. That could be using Java Applets to download the image and print using strange drivers etc. But if the image is enough why can't they just rescan the image?

Fundamentally you boss needs to rethink his or her approach to the project.

Now if you were to write a Perl script which would send the image to a print house along with a customer label. Then you could send printed images this way. In fact you could try a Perl driven Graphic-to-FAX-to-Mail routine. ;-)

Claude

a Non-Perl solutin(?)

I know I'm probably gonna get flamed for that... but I thought of one way to protect pictures from download and viewing offline.. you can use Macromedia's Flash.. :-s

I though of it when one of my friends wanted to put his images on the web but didn't want them to be downloaded..

here's the deal: (I suppose you know Flash)

• You make one movie with the picture on the main timeline at Frame 3.
• at frame one you load a movie with an absolute URL.
• at frame 2 you stop the main timeline.
• The Loaded movie tells the parent movie to goto frame 3 _level0.gotoAndStop(3);

This way, someone who is not online cannot view the picture, because the URL is absolute http://.../../movie.swf

I know, I know, Just hit on Print Screen button and you got a snapshot of the browser playing into the clipboard... oh well...

Real security on this?? you can't

There is a simple solution for what you want, and it comes from no stranger a source than Autodesk. For some years now there has been a special format for AutoCAD drawings called Drawing Web Format (DWF) which was designed especially for what you're talking about. On the downside it requires the viewer to have the (free) WHIP! plugin, but that provides a huge range of viewing features that could be helpful to your application.

On the cheaper end of things, I know of companies that only send JPGs of their drawings over the web. This works fairly well when the images are simple and don't change often, but you can imagine that the applications are limited. Municipalities like this approach to serving things like property maps which are very simple and rarely change.

--
I'd like to be able to assign to an luser