Any Method to save the free drawing as rtf format ?

[Michael Cheung]

I am new to ASP.net and i wanna get the idea how to do such task in
the web application.

In the webpage , i would like to display a photo so that the user can
draw freely on this photo. When the user finishs drawing, the free
drawing , excluding the photo content, can be saved as .rtf format. If
necessary, the user can load the free-drawing from the rtf format
file.

Thanks for your advice