C# App to stream part of desktop as ogg

I want a C# application that will allow the user to draw a rectangle on his desktop. Once the rectangle is drawn and confirmed - the application will act as a simple web server that will stream the rectangle graphics as an ogg video file (e.g. http://localhost/[login to view URL]) . The stream will not be a "frozen" picture, but a real stream of what's going on in that frame - for example if someone selected a rectangle around his web browser, the stream will show the sites he's visiting in near real-time. Resolution and fps should be user configurable. The ogg stream must be able to be played by VLC player remotely by providing the URL.