jQuery plugin to make round selection

Need something simulat jcrop plucgin (link to example is here: http://publikz.com/one-more-task-rounded-selection-in-jquery/) but with round (or ellipse) selection.

Can anybody help me? Maybe your开发者_运维百科 have made this in past. Need it to select round (ie have center & radius)

Thanks, Arsen

PS. Here is rectangular example:

Here is example. Drag the yellow pointer ... Round is also draggable ...
http://publikz.com/projects/roundsel-v2/

Yes, is not a finished yet, but anyone can take idea... and this is possible.