It is possible to provide a choice of background images for the LCD window on the IP phones. Choose Settings > User Preferences > Background Images on the phone in order to choose a background image.
The image choices come from PNG images and an XML file called List.xml that are stored on the Trivial FTP (TFTP) server the phone uses. In order to designate which background images are available, store PNG files and edit the XML file on the TFTP server. In this way, it is possible to make custom images available, such as a company logo.
The procedure on the Cisco CallManager 5.x remains the same as the procedure on the 4.x system. The only difference is that the images must be uploaded through the GUI instead of copied over to the TFTP Path folder. It is necessary to put the List.xml file and all images in the Desktops/320x212x12 folder since the directory structure of TFTP is predefined, which means there is no access to create folders. The directories do not show in the TFTP uploaded files list if they are empty.
Note: The List.xml file is case sensitive. Also, check the quotes (") and spaces in the file
Refer to With Cisco CallManager 4.0 (2), a background image is not displayed on the 7970 IP phones for more information on how to troubleshoot the background image on the IP phone.
IP Phone Models