Graphics Conversion Control

At this time, the Cisco IP Phone uses a proprietary format for image content, rather than using the widespread GIF and JPEG formats. This internal format is discussed in Chapter 4, “Using Cisco IP Phone XML Objects and Tags.”

The reason the phone does not support GIF images is simple. At the time the Cisco IP Phone was being developed, Unisys was still actively enforcing U.S. Patent Number 4,558,302, which covers the GIF file format. For better or worse, Cisco would have been required to pay a royalty to Unisys on every phone shipped with code that could render GIF images. The royalty and associated other costs (e.g. accounting) would have substantially increased the price of the phone.