I don't think there is anyway to implement. Although their names looks very similar. I think you should change a method to do this. Because one use Image Stream,another(WebControl.Image) use a ImageUrl. You've already got a System.Drawing.Image object,you can save it for a temporary file,then give the WebControl.Image instance correct path. Overload the Page's Render,after base.Render() then delete the temporary file. :-D Good luck!
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