fre:ac uses the following open source codecs and patches:

• CDIO Library v2.1.0: libcdio-2.1.0.tar.bz2
• CDIO Paranoia v2.0.0: libcdio-paranoia-10.2+2.0.0.tar.bz2

• Free Advanced Audio Coder v1.29.9.2: faac-1.29.9.2.tar.gz
  • Patch to fix an issue with Joint Stereo mode: faac-1.29.9.2-jsfix.patch

• Free Advanced Audio Decoder v2.8.8: faad2-2.8.8.tar.gz

• FLAC v1.3.2: flac-1.3.2.tar.gz
  • FLAC v1.3.2 metadata writing patch: flac-1.3.2-bitwriter.diff
  • FLAC v1.3.2 fast CRC processing patch: flac-1.3.2-fastcrc.diff

• LAME v3.100: lame-3.100.tar.gz
  • LAME v3.100 fast CRC processing patch: lame-3.100-fastcrc.diff
  • TMKK's AltiVec optimization patch: lame-3.100-altivec-20171014.diff
  • TMKK's SSE optimization patch: lame-3.100-sse-20171014.diff

• libav v12.3: libav-12.3.tar.gz
• libsamplerate v0.1.9: libsamplerate-0.1.9.tar.gz
• libsndfile v1.0.28: libsndfile-1.0.28.tar.gz

• Monkey's Audio 4.66: MAC_SDK_466.zip
  • Patch to build with the GNU Compiler on Windows: mac-sdk-4.66-gcc.patch

• MP4v2 v2.0.0: mp4v2-2.0.0.tar.bz2
  • Various fixes for all platforms: mp4v2-2.0.0-fixes.patch
  • Fixes specific to the Windows platform: mp4v2-2.0.0-win32.patch

• mpg123 v1.25.10: mpg123-1.25.10.tar.bz2
• Musepack r475: musepack_src_r475.tar.gz

• Ogg v1.3.3: libogg-1.3.3.tar.gz
  • Ogg v1.3.3 fast CRC processing patch: libogg-1.3.3-fastcrc.diff

• Opus v1.3.1: opus-1.3.1.tar.gz
• RNNoise 20171211: rnnoise-master-20171211.zip

• Rubber Band v1.8.2: rubberband-1.8.2.tar.bz2
  • Portability fixes for Rubber Band: rubberband-1.8.2-fixed.diff

• Speex v1.2.0: speex-1.2.0.tar.gz

• Vorbis v1.3.6: libvorbis-1.3.6.tar.gz
  • Patch to add aoTuV beta 6.03 optimizations: libvorbis-1.3.6-aotuv-b6.03.patch
  • Patch to add Lancer SSE optimizations: libvorbis-1.3.6-aotuv-b6.03-lancer.patch

• WavPack v5.1.0: wavpack-5.1.0.tar.bz2