GPAC is a multimedia framework based on the MPEG-4 Systems standard developed from scratch in ANSI C. The original development goal is to provide a clean (a.k.a. readable by as many people as possible), small and flexible alternative to the MPEG-4 Systems reference software. The natural evolution has been the integration of recent multimedia standards (SVG/SMIL, VRML, X3D, SWF, 3GPP(2) tools, etc) into a single framework. VRML97 and a good amount of the X3D standard have already been integrated into GPAC, as well as some SVG support and experimental Macromedia Flash support. GPAC also features MPEG-4 Systems encoders/multiplexers, publishing tools for content distribution for MP4 and 3GPP(2) files and many tools for scene descriptions (MPEG4<->VRML<->X3D converters, SWF->MPEG-4, etc...). This package is in Restricted repository because it incorporates MPEG-4 technology, covered by software patents.