Open the dictation formats that stayed locked for thirty years — Olympus DS2/DSS and now Grundig DSS — on any Linux box. No Windows, no GUI, no commercial software. A production recipe and the reverse-engineering trail behind it. 🔓
In one sentence: doctors, lawyers and police dictate into small voice recorders; the file format those recorders produce was kept secret for thirty years; this project opens it on any Linux machine — and gives the fix back to the open-source tools everyone uses.
→ Open the decoder and drag it in. Nothing to install, nothing uploaded — it runs inside your browser tab, and you can prove it by going offline first. Olympus DSS and DS2, Grundig DSS, encrypted files too.
Prefer to read before clicking? Start here — ten minutes, no background assumed.
A handful of strangers who never met opened a family of formats that doctors, lawyers and police have dictated billions of seconds into.
Part of it was already ajar, and we are careful to say so: Oleksij Rempel put a DSS-SP decoder into FFmpeg in 2014, and it worked. The rest was shut — DS2 entirely, and a Grundig variant that nothing on earth could read, not FFmpeg, not us, not even the commercial software. One person reverse-engineered the first piece; others made it portable. We put it in production over a weekend, and cracked the Grundig codec in an afternoon by interrogating the manufacturer's own decoder inside a debugger built from its DLLs.
Then we found that the part everyone assumed was solved had been quietly corrupting a whole class of recordings for years — in every open implementation, ours included. We diagnosed it wrong first, in public, and had to withdraw the patch. That chapter is the best one here.
All of it is in this repo: the working code, and exactly how it was done — including the parts where we were wrong.
Reference — what it does, the technical trail, where it stands, real-world numbers, what is in this repo, and credits.
MIT, same as the upstream codec. Fork, adapt, deploy — please keep attribution to the codec authors. We publish the clean reimplementations and the recovered specs, never the vendors' proprietary code.
Thirty years of locked, one bash command later. The chain has to keep going. 🔓