Copy an image from texture memry to framebuffer

I’d like to do a simple thing.
I have an image that I would like to draw as a background of me scene. I would like it to stay in video memory, and fastly blitting in the framebuffer. The way I do it now is binding it as a texture and then draw a big polygon. Is there a better way?
I guess I am asking for the inverse of glCopyTexImage2d…

Thanks a lot


PS: I posted the same messgae to the advanced board: I am desperate!