Can you clarify what you mean? Your post looks kind of rushed. however these are the two possible meanings I assume you are talking about.
A.) Accessing an image without it being uploaded on the server.
which would be done like this.
NPC Code:
with (findimg(###)) { this.image = "http://www.website.com/image.type"; }
B.) Drawing an image in graal and then exporting it out as a file type.
I dont really think that is possible but who knows.