Hacker News Reader

The audio codecs in use on Discord are exponentially more CPU-intensive than what was used on MSN back then, and there's no GPU offloading.

View on HN

I doubt they are using exponential time algorithms. They appear to be using Opus, which appears to be O(NlogN) worst case. Opus is also well known to be computationally cheap, like most (all?) audio codecs. It should run fine on the Pentium II.

I would be more concerned about modern video codecs. None of them are exponential time, but they need so much compute that it is unlikely that a Pentium II could handle them.

I'm not sure if Discord has options to fall back to H.263 like the open standards world (SIP) does, but that's the classic codec from 1995 and would definitely be usable on the CPUs of the time; if that's still too slow, then there's always H.261 (1988) which is basically "motion JPEG but with interframes".

You’re right and iirc it’s what Microsoft did with their NetMeeting that worked on Windows 9x (although poorly by today’s standards).

I’m pretty sure they didn’t mean “exponentially more” in the asymptotic complexity sense. They could be both O(N log(N)), but with dramatically different constants.

Reply on news.ycombinator.com