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GPAC is an Open Source multimedia framework for research and academic purposes. The project covers different aspects of multimedia, with a focus on presentation technologies (graphics, animation and interactivity

GPAC provides three sets of tools based on a core library called libgpac:

* A multimedia player, called Osmo4,
* A multimedia packager, called MP4Box,
* And some server tools (under development).

If you need a quick overview of GPAC capabilities, check out our videos or demos pages.

GPAC is cross-platform. It is written in (almost 100% ANSI) C for portability reasons, attempting to keep the memory footprint as low as possible. It is currently running under Windows, Linux, MacOSX, Android, iOS (iPhone and iPad), WindowsMobile, Embedded Linux (familiar 8, GPE) and some SymbianOS systems.

The project is intended to a wide audience ranging from students or content creators who want to experiment the new standards for interactive technologies or want to convert files for mobile devices, to developers who need players and/or server for multimedia streaming applications.

Features:

GPAC officially started as an open-source project in 2003 with the initial goal to develop from scratch, in ANSI C, clean software compliant to the MPEG-4 Systems standard, a small and flexible alternative to the MPEG-4 reference software. GPAC can probably be seen as the most advanced and robust 2D MPEG-4 Player publicly available worldwide, as well as a decent 3D player. 3D support is available on embedded platforms through OpenGL-ES.

In parallel, the project has evolved and now supports many other multimedia standards, with some good support for X3D, W3C SVG Tiny 1.2, and OMA/3GPP/ISMA features.

GPAC covers different aspects of multimedia: A/V codecs, network protocols and synchronization management algorithms, scene representation tools, etc… Here is a brief summary of the technologies implemented in GPAC in the packaging, playing and streaming areas.

Packaging Multimedia Content

GPAC features encoders and multiplexers, publishing and content distribution tools for MP4 and 3GPP or 3GPP2 files and many tools for scene descriptions (BIFS/VRML/X3D converters, SWF/BIFS, SVG/BIFS, etc…). MP4Box provides all these tools in a single command-line application. An exhaustive list of packaging features is available here but a good summary of what MP4Box can do for you is the following:

* MP4/3GP Conversion from MP3, AVI, MEPG-2 TS, MPEG-PS, AAC, H263, H264, AMR, and many others,
* 3GPP DIMS Packaging from SVG files,
* File layout: fragmentation or interleaving, and cleaning,
* File hinting for RTP/RTSP and QTSS/DSS servers (MPEG-4 / ISMA / 3GP / 3GP2 files),
* File splitting by size or time, extraction from file and file concatenation,
* XML information dumping for MP4 and RTP hint tracks,
* Media Track extractions,
* ISMA E&A encryption and decryption,
* 3GPP timed text tools (SUB/SRT/TTXT/TeXML), VobSub import/export,
* BIFS codec and scene conversion between MP4, BT and XMT-A,
* LASeR codec and scene conversion between MP4, SAF, SVG and XSR (XML LASeR),
* XML scene statistics for BIFS scene (BT, XMT-A and MP4),
* Conversion to and from BT, XMT-A, WRL, X3D and X3DV with support for gzip.

Playing Multimedia Content

GPAC supports many protocols and standards, among which:

* BIFS scenes (2D, 3D and mixed 2D/3D scenes),
* VRML 2.0 (VRML97) scenes (without GEO or NURBS extensions),
* X3D scenes (not complete) in X3D (XML) and X3DV (VRML) formats,
* SVG Tiny 1.2 scenes (including packaged in 3GP DIMS files),
* LASeR and SAF (partial) support,
* Progressive loading/rendering of SVG, X3D and XMT files,
* HTTP reading of all scene descriptions,
* GZIP supported for all textual formats of MPEG4/X3D/VRML/SVG,
* MP4 and 3GPP file reading (local & homepage