LADSPA
LADSPA is an acronym for Linux Audio Developers Simple Plugin API. It is an LGPLed standard interface for handling filters, effects and the like in Linux-based operating systems. It is used in many free audio software projects.
There are many other audio plugin standards, in fact most modern software synthesisers and sound editors will have their own and support for more common standards. Notable commercial standards are DirectX and Steinbergs Cubase Virtual Studio Technology.
LADSPA is unusual in that it attempts to provide only the Greatest Common Denominator of other standards. This means that its scope is restricted, but plugins written using it are easy to embed automatically in other software. The standard has changed very little with time so compatibility problems are rare.
LADSPA exists primarily as a header file written in the C programming language. There have been moves recently to introduce LADSPA onto software platforms other than Linux.
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