This might help you out on what you are trying to do:
First make an xpm image in 14 colors for 640x480 pixels.
You can use gimp to make a favorite picture or get a picture from somewhere. Then, do the following to convert the picture (ImageMagick is required.)
$ convert -geometry 640x480 -colors 14 filename.jpg filename.xpm
Then compress the 14-color 640x480 xpm file by gzip and copy it into /boot/grub.
Finally, edit /boot/grub/grub.conf as follows:
# Foreground color
foreground = ffffff
# background color
background = 000000
# Image to display
spalshimage = (hd0,0)/boot/grub/filename.xpm.gz
here's the full link to it:
http://www.momonga-linux.org/docs/gr...4.html#sec-4-6