I'm looking for some software that will allow me to create an animation of a given image being drawn in real time. For example, I have a jpeg. It's a picture of my pet dog, and I want some software that will create an animation (flash/gif/avi) of the image, but not the image fading in, rather, the image being drawn section by section. Anybody come across something like this?
There are several ways to fake this (very, very convincingly) in AfterEffects; I would suggest that. If you're using a raster image it'll be more difficult but what you'd essentially do is use the scribble and paint effects to fill in areas. If you have vector art (or can convert it to vector art using something like Live Trace in Illustrator) you can actually have After Effects fill the lines over time based on the vectors.
In any case, it's not a "click here and have the picture drawn" type of thing - to get a good accurate representation you may want to consider converting your artwork to vector artwork and going from there.
Corel Painter can actually do something like click here and have the image painted (Ok, adjusting some sliders required plus also setting up the scene a little). Here's a tutorial for doing it, and a little more: Corel Painter Auto-painting tutorial.
Now you might want to record it using another program that captures the screen as video file. I'll check a freeware for you later, kinda busy ATM.. (I'm quite sure Corel Painted doesn't supply such feature. Not 100% tho.)
You can do this with Flash as well, by using masks and applying shape tweens to those masks to expose the drawing a bit at a time. But probably more painstaking than using aftereffects.
Also, there is an Android app that does this called Paint Joy Pro, but at the moment there is no way to export the animation.
You should check out http://www.videoscribe.co/. They have a lightweight software that costs $12/month. I once had a project that involved whiteboard animation for an ad agency and the software was really helpful and quite easy to use. You can also check out tutorials on youtube for using the software