I had a quick google on the subject. Its not pretty.
Have a read through this discussion http://www.electrondepot.com/e.....22475-.htm
Quoting from one of the posts in the above discussion:
What probably hasn't been explained to you is the complexity of pulling
apart the composite signal then reconstructing it in to VGA (which is a
form of RGB format).
The most popular way is to digitise the composite video in to a video frame
buffer… and the reconstruct the VGA (RGB) analogue signal.
So you are going from analogue (composite) –> digital –>digital
This is a very high speed process and surface mount IC's with 100's of pins
All you need to convert VGA to composite is some passive resistors and capacitors, thats why its cheap. Going the other way requires active signal processing (its what happens in a TV between the composite input and the screen) and that isn't so cheap. In essence, its hard work and not to be undertaken lightly.
I do recall some sort of bodgework for a Beagleboard, but it wasn't said to work well…
So I assume there"s no reason why one of these type of adaptors wouldn"t work with the Rasberry pi. If so would it be the cheapest way to get a pi outputting to VGA?
Cheap converters are "ok" for allowing a video source to be connected to a VGA input only projector, but the quality of text on a computer screen will be eye-wrenching.
The other thing is that this has been discussed to death elsewhere on the forum. Have a look around. I'm now closing this discussion down.
edit: for clarification and to answer xalixos last post.
I'm just a bouncer, splatterers do it with more force.....