IETF CELLAR working group's repositories
matroska-specification
Matroska specification.
ebml-specification
the specification for the EBML format
flac-specification
The Free Lossless Audio Codec (FLAC) Specification.
flac-test-files
The Free Lossless Audio Codec (FLAC) test files
chair-notes
Agenda and minutes from virtual interim meetings. Also see: https://github.com/FFmpeg/ffv1