GPAC filters

Modern multimedia frameworks mix a variety of functionalities, such as network inputs and outputs, multiplexing stacks, compression, uncompressed domain effects and scripting, and require realtime processing for live services. They usually end up becoming very difficult to apprehend for end users and/or third-party developers, with complex testing and maintenance. The GPAC open-source media framework is no exception here. After 15 years of development and experiences in interactive media content, the possibilities offered by the framework were heavily restrained by a fixed media pipeline approach, despite the large number of tools available in its code base. In this paper, we discuss the major re-architecture undergone by GPAC to offer developers and end users a completely configurable media pipeline in a simple way, review the core concepts of this new design, their reasoning and the new features they unlock. We show how various complex use cases can now simply be achieved and how the re-architecture improved GPAC stability, making it a first-class candidate for research, commercial and educational projects involving multimedia processing.