Draw and safe an image

I'd like to use CImage class to paint a picture of 512x512 with random images then save it. I don't know if this is feasible. Someone can tell me how to do this ?

Thanks

CImage image;
image.Create(512, 512, 32);
HDC hdc = image.GetDC();
// Draw to hdc
image.ReleaseDC();
image.Save(...);

Thank you

I have another question

I'd like to draw that picture and also would want to draw its histogram at the same time. I am thinking about multithreading, but I am not sure I need it

So is this multithreading or is there a way simpler than that ?

Drawing should be always done in a main thread.
Histogram calculation may be done in a worker thread, if it takes significant time. You need realy large image to get long histogram calculation time. I don't think this is right place for multithreading.