Yes, there is an application that's capable of opening the WB1 file format to save it in JPG. The name of the software is XnViewMP and it can be obtained freely from the developer's website. Visit the URL below then scroll down and download correct version according to the OS type installed on your computer.
Install the application, and then right click your file and choose Open With. Select XnViewMP and the file should be opened. Use File > Save as to save to another format.
Application's website: http://www.xnview.com/en/xnviewmp/#downloads