There are a few conversions programs, but none of them are that great.
There is Triaxes, which is ok, but you need to use another program like Photoshop to create the depth map:
http://triaxes.com/I also got reasonable results from StPaint Pro, but its super expensive for no reason:
http://www.texnai.co.jp/eng/stereo3D/StPaint/index.htmlI have some aspirations of making my own software to do this (I even have an unreleased prototype floating around somewhere) but who knows when I will get time to finish that.