Gavl

Gavl, short for Gmerlin Audio Video Library, is a cross-platform multimedia library written in the C programming language. It provides a stable, high-level API for working with audio and video data, intended to be embedded in applications that perform playback, capture, editing, or processing of media streams. The library abstracts the details of codecs, containers, and device access behind a modular, plugin-based interface, enabling applications to work with different backends without changing their core logic.

Core concepts in gavl include streams, frames, and time bases. It supports demuxing and muxing of container formats, decoding and encoding of audio and video via interchangeable decoders and encoders, and synchronization across multiple streams. The library also offers basic image processing such as color space conversion and scaling, along with facilities for metadata handling, subtitles, and clock management to maintain proper synchronization during playback or processing.

Gavl has been used primarily by the Gmerlin multimedia project, but it is also employed by other open-source applications that require a portable, well-defined media API. It is designed to be portable across major platforms, including Linux, Windows, and macOS, and to integrate with common build systems.

Development of gavl has produced multiple releases since its inception in the early 2000s. As an open-source component, it is distributed under licenses compatible with embedding in a range of projects, and its API is intended to remain stable to support long-term integration by applications.