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- Get rid of INSTALL and README.txt
- Change references of Mac OS X to macOS

3RDPARTY.txt

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+Audacity is built upon other free libraries; some of these libraries may have
+come with Audacity in the lib-src directory.  Others you are expected to install
+first if you want Audacity to have certain capabilities.  Most of these libraries
+are not distributed under the terms of the GPL, but rather some other free,
+GPL-compatible license.  Specifically:
+
+  expat: BSD-like license.
+    Provides XML parsing.  Included with Audacity.
+
+  FFmpeg: GPL or LGPL (according to how you obtain/configure it)
+    Provides decoding/encoding of additional formats. Optional separate
+    download.
+
+  libid3tag: GPL
+    Reads/writes ID3 tags in MP3 files.  Optional
+    separate download as part of libmad.
+
+  libflac: Xiph.Org BSD-like licence (the parts we use)
+    Decodes and Encodes Free Lossless Audio Codec files. Optional separate
+    download.
+
+  libmad: GPL
+    Decodes MP3 files.  Optional separate download.
+
+  libmp3lame: LGPL
+    Encodes MP3 files.
+
+  libnyquist: BSD-like license.
+    Functional language for manipulating audio; available
+    within Audacity for effects processing.
+
+  libogg: BSD-like license.
+    Optional separate download, along with libvorbis.
+
+  libsndfile: LGPL
+    Reads and writes uncompressed PCM audio files.
+    Included with Audacity.
+
+  libsoxr: LGPL
+    The SoX Resampler library performs one-dimensional sample-rate conversion.
+
+  libvamp: new-style BSD
+    Plug-in interface and support library for audio analysis plug-ins.
+    Included with Audacity.
+
+  libvorbis: BSD-like license.
+    Decodes and encodes Ogg Vorbis files.  Optional
+    separate download.
+
+  lv2: a merging of the lilv (ISC license), lv2 (LGPL), msinttypes, serd (ISC), 
+    sord, sratom, and suil libraries to support LV2 plug-ins. 
+
+  portsmf: BSD-like license.
+    library for reading and writing midi files. Included with Audacity
+
+  sbsms: GPL v2
+    Pitch and tempo changing library. Included in Audacity
+
+  SoundTouch: LGPL
+    Changes tempo without changing pitch and vice versa.
+    Included in audacity
+
+  SQLite: Public Domain
+    Small and fast SQL database engine.
+    Included in audacity
+
+  Twolame: LGPL
+    Encodes MPEG I layer 2 audio (used in DVDs and Radio). Optional separate
+    download.
+
+  wxWidgets: wxWindows license (based on LGPL)
+    Cross-platform GUI library - must be downloaded and
+    compiled separately.
+
+
+For more information, see the documentation inside each library's
+source code directory.
+
+--------------------------------------------------------------------------------
+Additional copyright information:
+--------------------------------------------------------------------------------
+
+Nyquist
+
+Copyright (c) 2000-2021, by Roger B. Dannenberg
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+Redistributions of source code must retain the above copyright notice, this
+list of conditions and the following disclaimer.
+
+Redistributions of source code must retain the copyright notice, the
+list of conditions, and the disclaimer, all three of which appear below under
+"COPYRIGHT AND LICENSE INFORMATION FOR XLISP."
+
+Redistributions in binary form must reproduce the above copyright notice, this
+list of conditions and the following disclaimer in the documentation and/or
+other materials provided with the distribution.
+
+Redistributions in binary form must reproduce the copyright notice, the
+list of conditions, and the disclaimer, all three of which appear below under
+"COPYRIGHT AND LICENSE INFORMATION FOR XLISP," in the documentation
+and/or other materials provided with the distribution.
+
+Neither the name of Roger B. Dannenberg, Carnegie Mellon University, nor the
+names of any contributors may be used to endorse or promote products derived
+from this software without specific prior written permission.
+
+COPYRIGHT AND LICENSE INFORMATION FOR XLISP (part of Nyquist):
+
+Copyright (c) 1984-2002, by David Michael Betz
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+
+Redistributions in binary form must reproduce the above copyright notice, this
+list of conditions and the following disclaimer in the documentation and/or
+other materials provided with the distribution.
+
+Neither the name of David Michael Betz nor the names of any contributors may be
+used to endorse or promote products derived from this software without specific
+prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND
+CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.