OK, so I was kicking around a little for something to do.

http://www.nightwares.com/beta/xOrPixel.dir

This is Dir8.5 at the moment, as it is kind of a work in progress. 
About 160 Kb. Open source. However I've found that:

1. BitXOring pixels on images is pretty fast.
2. The image is NOT rendered to noise. Rather it looks like an 
effects color filter has been applied to it.

I tinkered more and then realized I don't need to retain the key pixel at all!

You might remember that since random numbers are algorithmically 
derived, if you set up your randomSeed to a known value when you 
begin (such as the h and w of an image!), you will get identical 
"random" results on two runs, provided you run the random operations 
in exactly the same way.

This is interesting because if you xOr an xOr you get right back 
where you started.

So I modified the file a bit and ended up speeding it up, with VASTLY 
satisfactory results:

http://www.nightwares.com/beta/xOrPixel2.dir

Do the xOr once and you get total garbage. Do it again and you get, 
ah, total garbage of a different kind.

I swear I did not cheat and hide the image someplace in RAM or an 
undo buffer. You can see for yourself by running this movie in 
Dir8.5, xOring once, saving the file and quitting Director. When you 
load the movie again the image will still be garbage. When you run it 
through the xOr filter a second time, it's restored.

So this, Chris, is one very nice way to prevent end users from 
frigging around with client bitmaps.

This is also of interest, I suspect, to anyone wanting to protect 
client images being stolen by DXR crackers.

Have fun. I am off to home now.

-- 

              Warren Ockrassa | http://www.nightwares.com/
  Director help | Free files | Sample chapters | Freelance | Consulting
        Author | Director 8.5 Shockwave Studio: A Beginner's Guide
                    Published by Osborne/McGraw-Hill
          http://www.osborne.com/indexes/beginners_guides.shtml
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