There is no program capable of converting JPEG images to contour lines. In order to obtain contour lines from an existing image, you'll have to perform several steps in a picture editing tool, such as Adobe Photoshop. First, go to the Image menu, Mode, Grayscale. Open your image in Adobe Photoshop, go to Filter, Stylize, hit Trace Contour and select an edge option. Choose a convenient threshold value and hit OK. You image should now be displayed in contour lines. You can do this with the help of any picture editor that integrates similar functions.