If you wish to customize the Encryption Desktop bootguard (pre-boot) screen you need to use an XPM (X PixMap) format image file.
Encryption Management Server administrators can add XPM format images to the Consumer Policy that applies to Encryption Desktop clients.
Custom background images must meet the following requirements:
XPM file sizes can be ten times larger than an equivalent file in popular formats such as PNG, JPG or GIF. However, Encryption Management Server compresses the XPM file when you upload it.
Below are some general guidelines on how to how to use the ImageMagick convert utility to convert an existing image to XPM format and how to use the GNU Image Manipulation Program (GIMP) to create a new XPM image.
ImageMagick is a free and open source application that can be downloaded here. In a Linux environment, ImageMagick can be installed using the Linux distribution's package manager.
If you have an existing image in a popular format such as PNG, JPEG or GIF you can convert it using the ImageMagick convert utility. For example, if your source file is image.png and you wish to create image.xpm run this command:
convert -depth 8 -colors 16 -resize 640x480 image.png image.xpm
If you wish to create a new image file you can do so using any image editing application. For example, Microsoft Paint. To change the image size in Paint, do the following:
GIMP is a free and open source application that can be downloaded here. In a Linux environment, GIMP can be installed using the Linux distribution's package manager.