updates .xvpics thumbnails from the command line

 This package includes a shell script and a C helper program to update
 XV/zgv/xzgv thumbnails from the command line.
 .
 Note that the thumbnails used by GNOME and KDE are in a different,
 incompatible format; you will need to use a tool designed for those
 desktops to create thumbnails for Nautilus or Konqueror.