Hi,
swftools is free software for all major OSs. Using Windows or Mac you can get a precompiled package there. Under Linux, most distributions have swftools already in there repositories. I installed that long ago on all three platforms, and as far as I can remember it wasn't complicated at all.
Having installed that you can use that software via command-line (eg. cmd.exe under Win). Then have a look how the programmes are used. It will be something like
swfextract -o myimages swffile.swf
. Just fiddle around a bit (it's fun).
You can then use what ever arguments you figured out in PHP via the command
system()
( http://www.php.net/manual/en/function.system.php ).
This all may sound a bit spooky at first, but it's not really rocket-sience. And if you need help, feel free to ask again (or even write a PM - as I'm currently quite stressed).
Hope I could help you now, dude.
Simon