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Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

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Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#71

Post by jeffbee »

Aloha wrote: post #55
reaperducer wrote: post #45

Earlier quoted context omitted.

I had the pleasure of using a real landline just before the pandemic. Honest wire-to-wire connection between two ranches, so no silly VOIP steps between. It was fantastic. You don't appreciate how much latency is destroying our ability to communicate verbally until you go back to the old way. One example is arguing. It's no wonder people used to be able to argue with one another on a telephone. You could raise your v…

A cell phone tbh, is about the same latency as a landline in most end to end call circumstances. Latency only really is noticeable when better than 600ms. (And only a real problem over 1000)

There is a huge quantity of research opposing your statements. The ITU considers 300ms round-trip latency to be catastrophic.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#72

Post by charlesdaniels »

This reminds me of a technology in Vernor Vinge's "zone of thought" series. I think they called it "evocations", where at the beginning of a call, a model is transmitted that allows the other end to re-construct what the sender would look/sound like from severely abridged data. It sure sounds plausible - the semantically meaningful parts of a conversation (video or audio) would appear to have significantly less entropy that all of the details captured by a mic/webcam. The fact that things like JPEG and MP3 exist are proof enough, and those (to my knowledge) aren't even feature-based.

Maybe N years from now, your {Skype,FaceTime,Zoom,Jitsi} call starts by transmitting a pre-trained auto-encoder that can reproduce your speech and visual appears with a "good enough" margin of error from a few kbps worth of data.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#73

Post by acdha »

Aloha wrote: post #55
reaperducer wrote: post #45

Earlier quoted context omitted.

I had the pleasure of using a real landline just before the pandemic. Honest wire-to-wire connection between two ranches, so no silly VOIP steps between. It was fantastic. You don't appreciate how much latency is destroying our ability to communicate verbally until you go back to the old way. One example is arguing. It's no wonder people used to be able to argue with one another on a telephone. You could raise your v…

A cell phone tbh, is about the same latency as a landline in most end to end call circumstances. Latency only really is noticeable when better than 600ms. (And only a real problem over 1000)

Do you have a citation for that? I've heard 200ms as the key threshold and the ITU uses 100ms for their default delay sensitivity class[1]. One key concept is that this isn't fixed but situational: if you're watching a TV show, the threshold is higher than if you're trying to react to something which is higher than simply noticing a delay and speech is more forgiving than, say, music hitting a precise tempo (I believe musicians have been tested as noticing delays down into the 10-20ms range).

One other big factor is consistency: if the variability is due to compressor overhead which is constant, the effect will be noticeable but less distracting than if it's varying due to something like wireless conditions.

1. https://www.itu.int/rec/T-REC-G.107-201506-I/en

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#74

Post by londons_explore »

walrus01 wrote: post #51
londons_explore wrote: post #41

Earlier quoted context omitted.

If they add it to WebRTC as they suggest, it will get auto-included in nearly all videoconferencing applications (most use webrtc under the covers, and a simple git pull will get it included in the next release).

They briefly mention the existence and current role of the webrtc codecs, but I don't see where they suggest they intend to contribute it or open it up as a library others can use.

If they don't release it as part of webrtc, they won't be able to use it in browser based videoconferencing. Google Meet/Hangouts on desktop rely on that.

While it is theoretically possible to process audio with something compiled with webassembly, data can't be marshalled into/out of a webassembly worker without the main browser threads help, and that tends to be too janky to use for realtime audio on most platforms.

That pretty much forces googles hand - if they want to use it in their web-based products, it must be opensource and available to all competitors.

They might say this feature only works with their mobile apps though.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#75

Post by colordrops »

rectang wrote: post #53
reaperducer wrote: post #45

Earlier quoted context omitted.

I had the pleasure of using a real landline just before the pandemic. Honest wire-to-wire connection between two ranches, so no silly VOIP steps between. It was fantastic. You don't appreciate how much latency is destroying our ability to communicate verbally until you go back to the old way. One example is arguing. It's no wonder people used to be able to argue with one another on a telephone. You could raise your v…

Between miserable latency, not-so-great fidelity, and the fecklessness of phone companies in the face of the robocall epidemic, I have come to hate phone calls. I'm rooting for something to replace phone communications. Any chance that Matrix can do better on any of those fronts? Especially on fidelity and latency since they're germane to the high-level subject of this discussion.

One conspiracy theory is that tech companies have lobbied to prevent real action on robo-calls, in order to get people like you to hate calls and migrate to online services.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#76

Post by jeffbee »

chrisseaton wrote: post #49
kevin_thibedeau wrote: post #46

Earlier quoted context omitted.

Just disable VoIP or disconnect from WiFi.

Isn't the actual phone network packet-switched and running over fibre optics now anyway? I don't think you can get a literally analog phone call anymore can you?

You probably can still get a real phone, but plugging a plain old phone into an optical network terminal, which converts to VoIP, has most of the virtue of POTS. I use a regular POTS device with Sonic fiber service and it sounds fantastic, with no noticeable latency.

Most of the problems with voice over mobile networks is caused by frame drops and wacky inter-arrival times. A wired IP network just doesn't have those problems.

Going back to the article/paper, I'd love to hear more about how Lyra interacts with Duo's machine-learned voice interpolation that fills in for dropped frames. Do they complement each other, or interfere?

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#77

Post by acdha »

bscphil wrote: post #58
boneitis wrote: post #23

I found the Lyra codecs in both examples easily the most difficult to comprehend, even compared against the scratchy Speex. Am I the only one? It is a little odd to me to see the praise here and on the previous discussion. To be fair, I am convinced I have APD (and, to be fair again, I have never got it checked out). E: Just realized there is a third example. Perhaps it is not as strong a statement due to Opus' doubl…

I personally wouldn't say "difficult to comprehend". I would say that the Lyra audio is "cleaner" but that the artifacts that there are, are louder and more annoying in Lyra. There's a very bad ringing effect and some flutter. If you personally find these artifacts distracting or confusing, I could very easily see the Lyra examples being harder to understand. I'm almost certain that Lyra has increased the volume on t…

I noticed the loudness, too, followed by a bit of a letdown with the subsequent odd artifacting. I was wondering whether that was also a factor in the user-perception ratings similar to how FM radio stations all started deploying compression to sound louder because it increased the odds of people favorably picking out their station while scanning through the spectrum.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#78

Post by LargoLasskhyfv »

reaperducer wrote: post #45
rectang wrote: post #39

What I want to know is whether Lyra takes any longer to encode than the alternatives. Because as far as I can tell, nobody cares in the slightest about latency. Phone calls are getting to be like writing postcards to each other. Speak in a whole paragraph. Wait several seconds for the latency to clear. Then the other party responds with a whole paragraph, waits several seconds for the latency to clear... Improvements…

I had the pleasure of using a real landline just before the pandemic. Honest wire-to-wire connection between two ranches, so no silly VOIP steps between. It was fantastic. You don't appreciate how much latency is destroying our ability to communicate verbally until you go back to the old way. One example is arguing. It's no wonder people used to be able to argue with one another on a telephone. You could raise your v…

Ever experienced european ISDN to european ISDN at 64kb/s ?

I know americans said 'I still don't need(it)' but I still do miss it :-)

Funny thing was I had better(and cheaper!) calls to the US using calling cards, dialing into Frankfurt, and from there to the US than using the native offer of my telco.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#79

Post by bscphil »

I've just taken a minute to confirm what my ears told me in Audacity. Please have a look at this screenshot: https://cloudflare-ipfs.com/ipfs/Qma41RMzieQ6ZGdGem9rLxnxEL1...

The Lyra version is clearly much louder. This is a serious problem and it borders on being reasonable to call it "cheating".

It's well known in the audio biz that if you ask people to compare two experiences, and one of them is a bit louder than the other, people will say that the louder one was better, or came through more clearly, or whatever it is you're trying to market for. For the purpose of comparing artifacts in two samples, it's absolutely crucial that they be the same volume. You might as well compare two image compression codecs where one of them "enhances" the colors of the original image.

Note: I took the clips for this comparison from the "clean speech" examples at the original source on Googleblog, not the blogspam.

Re: Lyra audio codec enables high-quality voice calls at 3 kbps bitrate

#80

Post by mlyle »

regularfry wrote: post #54
kixiQu wrote: post #52

Earlier quoted context omitted.

In the article, > This trick enables Lyra to not only run on cloud servers, but also on-device on mid-range phones in real time (with a processing latency of 90ms, which is in line with other traditional speech codecs). Does that not cover it?

It covers it, but it's not exactly brilliant. 200ms is the point at which conversation breaks down. If half that budget has gone on the codec, not much has to happen on the wire for it to be noticeable.

If your 200ms number is round trip, 90ms + 90ms is more than half that budget.
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