balrogg losslessly recompresses Ogg Vorbis and Opus files. Archives are typically 8-12% smaller than .ogg files and 3-8% smaller than .opus files. After decompression they are reconstructed identically.
The source code (GPLv3) and binaries are available here:
https://github.com/iczelia/balrogg.
Hopefully some find this useful. The Windows binaries are attached to the thread (64-bit, 32-bit modern Windows, 32-bit Windows 95 and newer).
Edit (06/09/26):
- v1.2 is now attached. It improves compression and decompression speed and memory usage. More slightly malformed files are accepted. Until v2.0 is reached, the releases will be neither forwards- nor backwards-compatible.
Edit (05/09/26):
- v1.1 is now attached. It slightly improves compression and decompression speed and memory usage. It also accepts more valid Vorbis and Opus files. Until v2.0 is reached, the releases will be neither forwards- nor backwards-compatible.