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Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

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Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#71

Too bad, like most other solutions, Jitsi, by default, shares screen at 5 FPS.

That's not been my experience. By default, it seems to adapt frame rate based on bandwidth. Some are 15 fps, some more, some less.

I was talking about screen sharing FPS. Not, the normal video FPS. I have plenty of bandwidth on my optic fiber connection. You can take a look at the situation @: https://community.jitsi.org/t/desktop-sharing-frame-rate-con...

and

https://community.jitsi.org/t/screen-sharing-fps/25132

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#72

I was told that Matrix/Riot is a good alternative to Jitsi (can share a meeting URL and offers E2EE). Does anyone have a data point here?

Riot isn't an alternative to Jitsi so much as a complement to it. Matrix is for text chat, and Riot uses Jitsi for calls; while you can embed a Jitsi client into Riot rooms, and it auto-shares the URL, AFAIK group calls are not E2EE even if the room is.

One-on-one calls through Riot _are_ encrypted, but only if made in a one-on-one direct chat.

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#73

Earlier quoted context omitted.

The Jistsi team says the server needs roughly 5.5Mbps per Chrome user. Firefox uses a lot more bandwidth, system resources, and degrades the room capacity. Just something to keep in mind, and after some testing I saw the same results. My AWS bill was projected to be over $1k/month, so I put it on Linode where it'll cost between $100-200/month. Just about any decent VPS provider would be good options compared to AWS d…

> The Jistsi team says the server needs roughly 5.5Mbps per Chrome user. That sounds like a lot! I wonder why an almost still image can use that much bandwidth, I guess it has to do with the low-latency requirement but I would love more details on that.

We use a technique called simulcast. It consists on making every participant "work a bit harder" for the good of the bunch.

That is, every participant sends 3 separate video resolutions to the server: 720p, 480p and 180p (this may change due to bandwidth constraints). Then the server will only forward the approopriate layer to each other participant. So, if you are only seeing me in a thumbnail it will only forward the 180p layer. If I become the active speaker (or you choose to pin me to the large view) the server will immediately switch to forwarding the 720p layer.

In addtion, we use SVC with temporal layers, so thumbnails may be given at just 15fps or even less.

We do have a trick up our sleeve (but IIRC it haad to be disabled for the time being) which involves disabling the ssimulcast layers that nobody is requesting. That is, if nobody iss seeing me in the large view, why send the 720p layer at all?

Hope that helps!

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#74

Earlier quoted context omitted.

That is only for 2 participants. For 3 or more (video participants), it uses the videobridge SFU. Source: https://github.com/jitsi/jitsi-meet/blob/master/doc/manual-i...

I had 4 people, so either the docs are wrong or they have forgone the video bridge on my server and are using their own.

If you had 4 people the video was going trhough the JVB for sure. Since a Jitsi Meet installation uses multiple components, maybe you didn't shut them all?

Video shenanigans can be a dark art, but not that magical ;-)

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#75
I wanted to evaluate it but was very put off when trying to connect to my google calendar they asked for full access to my Youtube profile. I get there is some youtube integration they have but binding those things together without any mention of why was enough for me to click cancel. Sucks because I really want to ditch Zoom.

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#76

Earlier quoted context omitted.

The Jistsi team says the server needs roughly 5.5Mbps per Chrome user. Firefox uses a lot more bandwidth, system resources, and degrades the room capacity. Just something to keep in mind, and after some testing I saw the same results. My AWS bill was projected to be over $1k/month, so I put it on Linode where it'll cost between $100-200/month. Just about any decent VPS provider would be good options compared to AWS d…

> The Jistsi team says the server needs roughly 5.5Mbps per Chrome user. That sounds like a lot! I wonder why an almost still image can use that much bandwidth, I guess it has to do with the low-latency requirement but I would love more details on that.

Almost still image is a weird way of saying “numerous still images regardless of amount of motion, that have to be stitched together in precise time sorted batches to provide a smooth experience for the viewer.”

Thinking about the use case it’s obvious this isn’t a simple calendar app amount of data.

I bet if you create some images in various resolutions these services support and what looks good to your eye, then fill folders with sequences of them, you’ll see why it’s a lot of bandwidth.

Better to over communicate and let the client deal with the organization as it’s designed to and not let some network admin nickle and dime over bits.

Financial economy doesn’t really say much about the literal economy of building all these toxic gadgets.

Given the big picture, not sure why such a trivial concern as bandwidths ephemeral money cost would foster such strong curiosity.

Even then, code is in a repo. Go learn.

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#77

I was told that Matrix/Riot is a good alternative to Jitsi (can share a meeting URL and offers E2EE). Does anyone have a data point here?

Riot isn't an alternative to Jitsi so much as a complement to it. Matrix is for text chat, and Riot uses Jitsi for calls; while you can embed a Jitsi client into Riot rooms, and it auto-shares the URL, AFAIK group calls are not E2EE even if the room is. One-on-one calls through Riot _are_ encrypted, but only if made in a one-on-one direct chat.

The riot features page makes it seem very "built-in" (https://about.riot.im/features#voice-video).

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#78
post #44

I like Jitsi because it doesn't require any signups and it's simple to create a channel/room. But the quality of video and audio seems a bit lacking. Does anyone have suggestions on how to improve Jitsi Meet's video and audio quality when working with the official smartphone apps and platform (not self-hosted)? Sometimes (on a broadband connection), for some participants, the video from a broadcaster freezes once in…

You can override configuration options by appending `#config.optionname=value` to the meeting url in a fresh new browser tab

Re: Jitsi Meet – Improving Scale and Media Quality with Cascading SFUs (2018)

#80
post #73

Earlier quoted context omitted.

> The Jistsi team says the server needs roughly 5.5Mbps per Chrome user. That sounds like a lot! I wonder why an almost still image can use that much bandwidth, I guess it has to do with the low-latency requirement but I would love more details on that.

We use a technique called simulcast. It consists on making every participant "work a bit harder" for the good of the bunch. That is, every participant sends 3 separate video resolutions to the server: 720p, 480p and 180p (this may change due to bandwidth constraints). Then the server will only forward the approopriate layer to each other participant. So, if you are only seeing me in a thumbnail it will only forward t…

Naive (and perhaps stupid) question here, why don't you request just the 720p feed from each participant and then rescale the streams as clients need them?
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