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Comment by motiejus | Hacker News Reader

Nothing about licensing or patents. I assume the worst (read: unusable for small businesses)?

10+ years ago I worked in a small voip shop, where we had very high quality (low jitter), but low bandwidth connection. I researched many codecs of the time (2010-ish).

We liked speex, because it can be used "without strings attached". Also, I can choose the quality depending on the bandwidth. Although for low bandwidth g729 was better. Which we couldn't use because of royalties (but allowed myself to test it).

We chose alaw/ulaw when bandwidth was not a concern, and speex when it was.

Since it does not mention usability outside of google, I also find this comparison unfair or incomplete: if you are comparing a proprietary codec, compare it to g729. If you are comparing a codec to speex, it should be open/free.

Edit: grammar

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These days the correct comparison would be to Opus, which is similarly unencumbered and performs fantastically at low bitrates (and has a speech specific mode for even lower bitrates, because it's a hybrid of two codecs). It's also extremely low latency, so there's now no reason to accept trade-offs. (For the same bitrate as alaw/ulaw, you can get high quality full band music with Opus.)

These days it's more or less the standard for realtime voice. WebRTC uses it, most of the popular realtime voice applications use it as well, as does Signal.

They did compare to Opus.

I wouldn't be as pessimistic—they invented VP9 and were important to AV1, and continue to promote both and use them everywhere.

I am curious about this as well. With all the debates in the threads here about this codec, I think it would be worth having the folks at Mumble [1] (murmur server) incorporate it as an option so people could fire up an instance and put it to the test. That of course only works if the license is compatible. They compare the performance to Opus which is used currently by Mumble.

[1] - https://www.mumble.info/

The G.729 patents are now royalty-free btw:

https://web.archive.org/web/20170202062530/http://www.sipro.... https://en.wikipedia.org/wiki/G.729

> Nothing about licensing or patents. I assume the worst (read: unusable for small businesses)?

If there's a free software implementation, and a company offering the service based in the EU (or shop around and find any other jurisdiction where software patents don't matter), it's often YOLO - but call that "legal arbitrage" if you want to sound fancy :)

What are the current choices for "CD quality" speech compression (lossy but indiscernible) at the moment? Just had a discussion with a friend of keeping an always-on speech recorder on and wondered about disk space consumption.

Basically Opus (Vorbis successor) or AAC (MP3 successor).

A fair point if you're evaluating actual usage rather than just quality, but Google isn't going to be only one with this sort of codec. We can expect better free versions to come along in time.

With good enough licensing it could possibly replace speex.

It is sad that we have to think about licensing and patents of technologies instead of only how good or advanced they are.

I'm over here preferring g711/ulaw because I prefer the hard roll off at 4kc.

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