Alright, I wrote a blogpost about my adventures:

This doesn't have much new compared to my posts from this weekend, but here they are ordered and coherent.

I also posted some audio samples:

Keep in mind that both samples will sound pretty much horrific, but also that each sample is around 100kb for more than a minute of audio.

I prefer the Opus file to the mp3 file, as it's a little less muddy during speech (but ruins music.)

@ajroach42 POTS audio is only 64Kbps, uncompressed. I'm surprised modern compression can't get way better than that.

@tek Oh, we can. If you want to devote some serious power to playback, stuff like Codec 2 can apparently deliver pretty stunning results.

And VoIP codecs can do some pretty interesting stuff, too, but none of those play back on vintage hardware.

@ajroach42 @tek TBH I wonder how much power is necessary - AFAIK they're doing realtime encode and decode on a 160ish MHz Cortex-M4 with time to spare, and that's in a RAM-tight environment.

In a RAM-heavy environment like an old personal computer, you might be able to implement some of the algorithms as lookup tables (if they aren't already) and make it even faster?

@bhtooefr @tek I am unfortunately not equipped for this discussion.

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