ffDiaporama allows you to produce joint files during the rendering process.

The following files are availables:
Thumbnails A video or music file can be accompanied with an image file which must have the same name but with the .jpg extension (example: holidays.mkv and holidays.jpg in the same folder).
This image is called a thumbnail and is used as icon for this file by ffDiaporama and many Media Center Systems
XBMC .nfo files The .nfo file for XBMC allows XBMC to recognize the rendered videos as movies.
For more information see: XBMC nfo files