Is it possible to take a snapshot from an existing image?

We can take screen shots from any portion of the screen using Graphics.CopyFromScreen Method in C#, but that's for situations where we have a visual form.
I want to know if it is possible to create a virtual screen (like a new desktop but a hidden one), displaying the image inside it, and then take the screen shot of the specific area where the image is, as it is looks and displayed and then save the resulting image.
Is such a thing possible?