There are a lot of such programs called vectorizers.
I used some of them several years ago (don't remember the names).
Choose any you like: http://www.google.com/search?q=vectorizer
... of converting JPEG images to contour lines. In order to obtain contour lines ... to Filter, Stylize, hit Trace Contour and select an edge option ... should now be displayed in contour lines. You can do this ...
