Creating your own Plug-in

Audacity is designed to support plug-ins that extend its functionality.

How to choose which kind? It depends so much on what you want to do and what your programming background is. The big choice is between C/C++ or a scripting language. Generally, you can get started much much faster with any of the scripting languages, however you lose some flexibility in what you can do. LADSPA, VST and Vamp plug-ins are all usable in other programs besides Audacity, which is a big plus. However you can only use them as effects to alter sound or analyse it, not to add new toolbars to Audacity.

There isn't yet a lot of documentation on developing for Audacity. We're gradually improving our developer guide.

Nyquist
There is a built-in XLisp interpreter that is used mainly for creating new sound effects. It can also be used to create labels. It's mature, stable, and has been in Audacity from the start. See Nyquist. Updated Nyquist documentation is available in the German forum (documents are in English language).

Batch Chains
Limited ability to do 'the same thing' to a large number of files. Originally written for cleaning up lots of audio tapes, applying noise removal, removing long silences too and converting to mp3. Stable, but limited to 'doing the same thing' over and over.

Perl
Still somewhat experimental. More information here. It's best to ask on the developer list before getting into this.

LADSPA
Sound effects. C or C++, Ladspa Plug-in. GUI is built from simple instructions.

VST
VST Plug-in. GUI is built by the plug-in directly.

Vamp
C or C++. GUI is built from simple instructions. Similar in concept to LADSPA except this it is designed particularly for analysis of sound, so for example finding particular words in a spoken text. Vamp is a recent addition to Audacity. CVS head now has Vamp support compiled in by default. Vamp is written by Chris Cannam who developed it for his Sonic Visualiser program. The plug-ins work both in his visualiser and in Audacity. If you're interested in developing a new Vamp plug-in for Audacity you should join the.

Hi-Jacker
Plug-in that takes over the entire GUI of Audacity and uses the underlying services for its own ends (not to be confused with the POSIX sound server called ). Hi-Jacker has been used successfully in the Audacity-Extra project on Sourceforge. The code to support hijacking plug-ins is in CVS HEAD, but is not compiled in by default.

Audacity Modules
Work in progress, a proof-of-concept on Windows, Linux and Mac. It's a still experimental method for adding any feature to Audacity as a plug-in. The plug-in can use any exposed feature of Audacity, and of wxWidgets, and it will have a more complete API for interaction with the Audacity program as it develops.

We highly recommend the main trunk of the current code repository as the basis for developing new modules. Developers must use the Audacity code base from version 1.3.5 or later to get this support. See Modular Architecture Initiative for an overview.