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How would it be any different from any other e2e group chat?

by opless 7y ago

viraptor 7y ago
You have to send all available qualities of the stream yourself. Normally the server does the recompression for lower qualities. That means: more processing power and more bandwidth needed. Where normally you'd be able to send 720p, now your device may not be able to handle doing both that and lower quality (2-3 streams) at the same time. This multiplies again with screen sharing. Basically it's doable, but if you can prevent people complaining about the fans taking off and the CPU usage... why would you risk it?
- opless 7y ago
  Ugh. Multiple compression streams? Why? 720p would be too much IMHO.
  - jdietrich 7y ago
    >Multiple compression streams? Why? Zoom automatically switches between quality levels based on your connection speed, who's talking and the size of the viewport. 720p would look fairly rough when fullscreened on most non-mobile displays, but it's orders of magnitude more than necessary when viewed as a thumbnail on a mobile device. Making multi-user video work in a mostly seamless fashion is a surprisingly hard problem. Using a single stream would substantially degrade the experience, which may be a worthwhile tradeoff for high-security environments but certainly wouldn't be a worthwhile tradeoff for most users.
  - viraptor 7y ago
    720p is the standard laptop camera these days. You notice if anyone streams less. Next, desktop sharing is going to be at least 1080p. Then you need to have lower resolutions for anyone who can't handle that much on their connection. Same for desktop share.
  - simonh 7y ago
    It's not just about the resolution, but also the bitrate and fps. Perceived video quality is a big deal to companies like Zoom. I don't blame them for not using E2E, it's a tough technical issue, but I do blame them for lying about it.
  - nonninz 7y ago
    > 720p would be too much IMHO. I may be spoiled with a good real 50/10 Mbit connection but for me in 2020 720p is the bare minimum. Expecially when screen sharing.
- michaelt 7y ago
  H.264 has a spec for 'scalable video coding' [1] where one stream can contain multiple quality levels, allowing a video's quality to be reduced by just selectively dropping packets. (No idea how widespread encoder/decoder support is compared to vanilla h264 though) [1] https://en.wikipedia.org/wiki/Scalable_Video_Coding https://en.wikipedia.org/wiki/Scalable_Video_Coding
  - viraptor 7y ago
    That's pretty cool. I wonder how well does it work with bidirectional communication. It sounds like for just sending/receiving where you can saturate the link, that would be awesome.
  - _-___________-_ 7y ago
    Wow, that is awesome. I know what I'll be spending some coronatime doing!

How would it be any different from any other e2e group chat?

by opless 7y ago

How would it be any different from any other e2e group chat?

You have to send all available qualities of the stream yourself. Normally the server does the recompression for lower qualities. That means: more processing power and more bandwidth needed. Where normally you'd be able to send 720p, now your device may not be able to handle doing both that and lower quality (2-3 streams) at the same time. This multiplies again with screen sharing. Basically it's doable, but if you can prevent people complaining about the fans taking off and the CPU usage... why would you risk it?

opless 7y ago
Ugh. Multiple compression streams? Why? 720p would be too much IMHO.
- jdietrich 7y ago
  >Multiple compression streams? Why? Zoom automatically switches between quality levels based on your connection speed, who's talking and the size of the viewport. 720p would look fairly rough when fullscreened on most non-mobile displays, but it's orders of magnitude more than necessary when viewed as a thumbnail on a mobile device. Making multi-user video work in a mostly seamless fashion is a surprisingly hard problem. Using a single stream would substantially degrade the experience, which may be a worthwhile tradeoff for high-security environments but certainly wouldn't be a worthwhile tradeoff for most users.
- viraptor 7y ago
  720p is the standard laptop camera these days. You notice if anyone streams less. Next, desktop sharing is going to be at least 1080p. Then you need to have lower resolutions for anyone who can't handle that much on their connection. Same for desktop share.
- simonh 7y ago
  It's not just about the resolution, but also the bitrate and fps. Perceived video quality is a big deal to companies like Zoom. I don't blame them for not using E2E, it's a tough technical issue, but I do blame them for lying about it.
- nonninz 7y ago
  > 720p would be too much IMHO. I may be spoiled with a good real 50/10 Mbit connection but for me in 2020 720p is the bare minimum. Expecially when screen sharing.
michaelt 7y ago
H.264 has a spec for 'scalable video coding' [1] where one stream can contain multiple quality levels, allowing a video's quality to be reduced by just selectively dropping packets. (No idea how widespread encoder/decoder support is compared to vanilla h264 though) [1] https://en.wikipedia.org/wiki/Scalable_Video_Coding https://en.wikipedia.org/wiki/Scalable_Video_Coding
- viraptor 7y ago
  That's pretty cool. I wonder how well does it work with bidirectional communication. It sounds like for just sending/receiving where you can saturate the link, that would be awesome.
- _-___________-_ 7y ago
  Wow, that is awesome. I know what I'll be spending some coronatime doing!