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Comment by SynAck6 | Hacker News Reader

I can potentially see VR create a demand for such high bandwidth. With high resolution fully immersive videos perhaps

You won't need anything more than Stadia for that

> An internet connection speed of 10 megabits per second (Mbps) or greater is the minimum recommended to use Stadia. A slower network speed can cause issues while you play games.

> To play at up to 4K resolution, you'll need an active Stadia Pro subscription and a network speed of 35 Mbps or greater. Check below for hardware requirements.

That's the current requirement for the compression they use. I'm sure that there's a lot of heavy optimizations under the hood to support 4K at 35Mbps, which is most likely lossy as well.

Bluray video requires about 144Mbps at the highest quality right now. A bulk of this can also be audio formats with spatial information, like Dolby Atmos, or DTS:X.

VR might need even twice that amount for both eyes. Combine that with more dense sensors, probably improvements in processors and memory allowing better lossless decoders, and you can cross 1Gbps easily. I can also see multiple users at home needing this at the same time.

100mbps h264 is fine. In fact, for existing content we got mostly indistinguishable results at 50mbps. H265 gives you another 30%.

Now there might be people who can notice the difference but in our limited human studies testing on in house VR employees they couldn’t (try it out yourself if you have an Oculus link - the Oculus PC tool lets you adjust the bandwidth live if I recall correctly). You do want to start initially with a high bandwidth so that the initial P frame gets the most detail and then you can decrease the bandwidth which applies to the subsequent I frames.

Obviously VR resolution keeps increasing every year or two so this will grow but you’ve got other techniques that combat this like ML supersampling.

I think an overlooked piece of 10GBe is lower latency and more consistent performance as packet scheduling is the most challenging aspect of streaming VR. There could also be other use cases where higher bandwidth is more critical but video streaming VR likely isn’t it.

VR Streaming is impossible. The latency is nausea (and vomit) inducing. I don't mean that as an hyperbole, it really is.

That sounds like you're still streaming in traditional 2D with a static viewpoint being rendered somewhere in the cloud.

Full pre-rendered VR streaming would need to ship video of the entire environment for both eyes (or a reasonably large subset), and the client would be responsible for rendering your point of view. There'd be no latency that way, but the bandwidth needs would be significant given 4K per eye and a 90-degree FOV. That's on the order of 16K per eye, or 32K @ 120Hz video for static location. Add on some extra bandwidth for volumetric video to support position tracking, and you're looking at some even sillier numbers. Granted, a headset might spontaneously combust with that kind of data rate.

You can only accelerate your head so fast. Whatever resolution you pick for your headset, expanding the area by 50% is probably more than enough to let the client compensate for movement.

Cool to hear that what I do almost every day is impossible :)

AirLink actually works really well for me, but it does need a clean 5Ghz channel with nothing else on it. Any other device that is connected (even if it's not doing anything) will cause stutters. I have a separate Unifi 6 Lite AP hanging right above my head for it with a separate SSID.

Are you streaming across the room or actually from a datacenter? The impossible part seems to be that there is some latency that is pretty much unavoidable when you stream from 500km away.

Across the room normally but I signed up with plutosphere as well which offers VR streaming from the cloud. I have yet to try it because they have some capacity problems, but initial feedback from users that got in were good. I want to try it mainly to evaluate and for travelling as I already have a great game PC.

But latency does not seem bad enough there to worry about. Not everyone is as sensitive to that anyway and once you have your VR legs it becomes even easier.

I prefer local computing over streaming anyway. But like I said for travelling it might be a great option.

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