how i can create a image from a opengl view

My main problem is obtein an image more big that the view. Someone can help me?

I’m not sure what you mean.Do you mean your resolution is say 640x480 but you want to get a snapshot in say 800x600 or larger?If so I think you might want to take a look at the Red Book,3rd chapter in “Perspective Projection” where it says advance(right under fig. 3-13 I think).Hope that helps.