Associated previously with Internet video piracy, DivX Networks released DivX Version 5.0 this week in its bid to challenge the supremacy of Internet video formats like Windows Media, RealPlayer, and Apple Quicktime. Self-dubbed the "Mp3 of Video," DivX offers additional functionality from previous versions, including image quality improvement, MPEG-4 compatibility, and faster performance. Three versions of the Windows software bundle (encoder and decoder included) are available: DivX, the free version; DivX Pro, a $30 version that offers advanced encoding and video tools; and DivX Pro (Ad-Supported), a free version of DivX Pro that has pop-up advertising banners. Windows 98/Me/NT/2000/XP and DirectX 7.0 drivers are required. DivX Networks also provides software for Mac and Linux. Both Mac OS and Linux users can download bundles that include "DivX Playa," the decoder for DivX-encoded files. Mac OS users will not be able to encode in the DivX format though; only the Linux bundle has encoding capabilities.