Audio plugin

An audio plugin is a dynamically linked library containing digital signal processing or sound synthesis functionality, which can be loaded by a computer program at runtime.^[1] Audio plugins usually provide their own user interface, which often contains GUI widgets that can be used to control and visualise the plugin's audio parameters.^[2]

The program used to dynamically load audio plugins is called a plugin host. Example hosts include Mainstage, Bidule, REAPER and Sonic Visualiser. It has also been shown that plugins can be used to host other plugins.^[3]

Plugin types

There are three broad classes of audio plugin: those which transform existing audio samples, those which generate new audio samples through sound synthesis and those which analyse existing audio samples.^[4] Although all plugin types can technically perform audio analysis, only specific formats provide a mechanism for analysis data to be returned to the host.^[5]

Software architecture

Communication between host and plugin(s) is determined by a plugin API. The API declares functions and data structures that the plugin must define in order to be usable by a plugin host. Additionally a functional specification may be provided, which defines how the plugin should respond to function calls, and how the host should expect to handle function calls to the plugin. The specification may also include documentation about the meaning of variables and data structures declared in the API. The API header files, specification, shared libraries, license and documentation are sometimes bundled together in an SDK.^[6][7]

Plugin formats

See also

• Plug-in (computing)
• Effects unit

References