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

• CDIO Library v2.1.0: libcdio-2.1.0.tar.bz2
• CDIO Paranoia v2.0.1: libcdio-paranoia-release-10.2-2.0.1.tar.gz
• FFmpeg v4.4: ffmpeg-4.4.tar.xz
• Free Advanced Audio Coder v1.30: faac-1.30.tar.gz
• Free Advanced Audio Decoder v2.10.0: faad2-2_10_0.tar.gz
• FLAC v1.3.3: flac-1.3.3.tar.xz

• 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

• libfdk-aac v2.0.1: libfdk-aac-2.0.1.tar.gz
• libsamplerate v0.2.1: libsamplerate-0.2.1.tar.bz2
• libsndfile v1.0.31: libsndfile-1.0.31.tar.bz2

• Monkey's Audio 6.29: MAC_SDK_629.zip
  • Patch to build with the GNU Compiler on Windows: mac-sdk-6.29-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 v1.28.0: mpg123-1.28.0.tar.bz2
• Musepack r475: musepack_src_r475.tar.gz
• Ogg v1.3.5: libogg-1.3.5.tar.xz
• Opus v1.3.1: opus-1.3.1.tar.gz
• RNNoise 20190904: rnnoise-master-20190904.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 v1.3.7: libvorbis-1.3.7.tar.xz
  • Patch to add aoTuV beta 6.03 optimizations: libvorbis-1.3.7-aotuv-b6.03.patch
  • Patch to add Lancer SSE optimizations: libvorbis-1.3.7-aotuv-b6.03-lancer.patch

• WavPack v5.4.0: wavpack-5.4.0.tar.bz2