I've google already, but come up with nothing.

How would I save the data (in mysql I guess...although I'm open to ideas) from a drawing app like this:

http://www.sitepoint.com/article/create-flash-sketchpad

so that show it again like this:
http://www.inanyus.com/ecard/

I don't want to make ecards....just save the picture someone has drawn and redisplay it like above.

Can any point me in the right direction / tell me how hard it'd be?

Thanks in advance!