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Comment by pxx | Hacker News Reader

I've worn an Oculus Quest 2 on an airplane to watch 3d movies. It works fine. This article is way too deep of a dive on non-issues.

* Sure, you don't get the full resolution. The apps typically put you in a virtual movie theatre and "waste" pixels on your environs. But people watch 720p content all the time! Would I want this to be my only media experience? No. Is it better than your tiny phone or cheap tablet on your tray table? Yes.

* The 6dof tracking is totally off because the cameras can't see the fact that you're moving and you just end up shifting wildly. You can turn it off and go back to accelerometer-based head tracking and it works fine (modulo landing and takeoff, and in those regimes you just need to reset the viewport every so often). I would recommend you turn off 6dof before you get on the plane though; it's wild trying to do it on the plane.

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>But people watch 720p content all the time!

I'll do you one better. My nephew was going to a summer camp that didn't allow the kids to bring phones or tablets. He was allowed to bring an MP3 player, tho. So I downscaled a copy of Into the Spiderverse to 432x240 (his iPod Nano's native resolution). I left the bitrate quite high (1600kps) and it looks absolutely great. Even stretched out on a full sized ipad, it's completely watchable.

> My nephew was going to a summer camp that didn't allow the kids to bring phones or tablets. He was allowed to bring an MP3 player, tho. So I downscaled a copy of Into the Spiderverse to 432x240 (his iPod Nano's native resolution).

You may have been inadvertently subverting his summer camp experience.

Maybe he will get caught as part of the summer camp experience. I think transistor radios at summer camp were thought to ruin the experience.

As a summer camp alumnus myself, I can assure you that finding clever ways to circumvent camp rules is itself a cherished camper tradition.

Sometimes a little bit of comfort makes being away from home easier on kids and makes the summer camp experience a positive one.

I've said this before, but people process resolutions wrong. Resolutions are not a promise of a minimum of quality, they are a maximum. High quality pixels at lower resolution can stand up to more processing for upscaling than garbage ones. A resolution tells when you'll top out because you've got near-100% fidelity for each one.

I have a bit of astigmatism, but I still don't wear glasses as a routine thing, and when I watch good DVDs on my 60" TV from about 8 feet away, it's fairly rare for me to be that upset by the video quality. Even after I suck some out downsampling into mp4, it's still rare for me to actively notice. DVD encoders are fairly good now.

At this point I don't care at all if something advertises a "4K" stream because I know that it's still likely to be not all that good. Tell me the bitrate of your stream, that's what I want to know. (Assuming the use of a modern codec and quality encoder.) I can get a "4K" stream with hundreds of kilobits per second. The encoder will be crying because of the shoddy job you're making it do and the decoder will look at you like you're on crack, but by golly, 4K's worth of pixels will indeed be shoveled onto the screen.

I totally agree and would go so far as to say that the 4k streams look like shit compared to good HD DVDs because they're.

Take an average 4k Stream from YouTube/Netflix/etc and look at the transfer size for the full duration. It's gonna be something around 1-3gb per hour from my observations.

A good 4k Video is usually around 5-10x that size and with good reason, because the resolution demands a lot of bits to make it shine, no matter how well you've encoded it

> High quality pixels at lower resolution can stand up to more processing for upscaling than garbage ones.

What does "high quality pixel" mean?

Bit rate vs compressed (think of jpg artifacts)

It means an actual pixel stored in data (such as in a key frame) rather than a generated pixel (such as in an interpolated frame). The amount of data generated for interpolated pixels is usually the bare minimum required; for some devices it's literally just a change in value from the previous frame.

It may be easier to think about high-quality swathes of pixels, because obviously any one pixel can't be wrong in isolation, and even to the extent it is, who cares.

However, if you look at a swathe of pixels, say a 16x16 chunk, you can reasonably talk about with what fidelity that set of pixels represents the original signal, whatever that original signal was. You get into the whole perceptual coding thing which tells us that determining the human-perceived accuracy of a chunk of pixels is more than just adding up the differences, but you can take that as a suitable first approximation for thought.

High-quality pixels have minimal deviation from the source material. Low-quality pixels have significant deviation.

Tom Scott has a good video where turns up and down the quality live so you can see it in a single video: https://www.youtube.com/watch?v=r6Rp-uo6HmI The video's resolution never changes, and you could say the video's bit rate never changes (it probably does because adaptive coding saves YouTube a fortune, but conceptually you could say it doesn't), but the quality of the pixels sure does.

Agree completely. The author also suggests that you don't want "see through" mode coming on everytime someone walks by, but that's exactly what I want. I don't want to be in a public area, even a plane, unaware of my surroundings.

If I'm watching on a 7" screen on a seatback, I still have peripheral vision. I want to maintain that. I want to see on the area that isn't the screen, I just want something bigger than 7", and the ability to do things besides just watch movies/TV (like, my own content or games....).

Basically, this is clickbait.

Lower video resolution also feels like a decent tradeoff for a few reasons:

- Thanks to the headset's optics, you're staring at a point in space ~5ft in front of you instead of a couple feet tops which cuts down eye strain

- It's private, so you don't feel like people are watching over your shoulder

- On international or redeye flights, you're not keeping everybody up with the light spewing from your tablet/phone

> On international or redeye flights, you're not keeping everybody up with the light spewing from your tablet/phone

On almost every international overnight flight I've been on people watch movies and TV on seat back monitors at all times. For people who need absolute darkness the airline usually provides an eye mask.

> Is it better than your tiny phone or cheap tablet on your tray table? Yes.

I hadn't thought of that. As a fairly tall person, working on a laptop or tablet on a plane has become a literal pain in the neck. I don't know if it's that the seats are closer, the tray tables are lower, or maybe I'm just getting old. This seems like a much more pleasant experience.

Some nights I'll wear my headset in bed for this reason. I've got a TV in my room, but with my Quest I can lay back however I want and still get an IMAX display in front of me.

Not sure if I'd be desperate enough to try it on a plane (the stereoscopy would probably make me sick), but as a viewing experience it's phenomenal. The OLED panel on the original Quest is a godsend for movie watching, and when streaming over DNLA I can get 3-4 hours of battery life.

Yup I do the same. The key is an app that doesn't use the "movie theater" gimmick but just gives you a screen you can resize arbitrarily and move in space to vertically above your head.

It truly is a glorious viewing experience, and if you make the screen large enough you effectively get full 1080p detail.

For me it's how close the seats are, you have to hold your hands in close to your body to type on a keyboard, and you don't have the room to tilt the screen back for a good viewing angle.

Sometimes I've found resting the laptop in my lap/knees along the screen hinge (so it makes a 45 degree angle with my thigh) to be the most usable. This requires you to pull your shoulders/elbows back however so you usually can't do it if you have someone you don't know sitting next to you.

I have strongly debated bringing my Quest 2 onto a plane and using a wireless keyboard to program with, I think the ergonomics would work out much better when flying coach.

> But people watch 720p content all the time!

I had the same reaction, and the article only says that the effective resolution, accounting for their "pixels per degree", is something less than 1080p. Which sort of implies it is better than 720p...somewhere between the two. Plus whatever benefit blocking out the things around you in the plane has.

I'd much rather hear some reviews of the experience from run of the mill people that don't have much experience with VR.

I suppose the article does, though, at least set a reasonable expectations bar.

My interpretation is that it is some sort of cognitive bias, which is very common: Because A is better than B, we start to think of B as not good, while in reality B is still good and A is just better. In particular A may only be marginally better, or only be better on paper, according to an irrelevant metric.

I see this come up a lot in hardware discussions (Megapixels come to mind) and manufacturers love to jump on this effect.

Could the Vision pro just track you based on your environment rather than the accelerometer while on a plane? That would prevent any kind of drift. If that R1 chips is as fast as they say then that doesn’t seem unreasonable.

Based on what they have said in interviews, I have a feeling that is exactly what they are doing.

My guess is that they combine a number of signals to do the tracking, and when those signals start to disagree too much they've prioritized some signals over others. That could include things like how your eyes are tracking and other physiological signals, not just the accelerometer and various cameras.

This is what the Meta and Windows MR headsets do as well, it's not even that intensive.

Most inside-out headsets like the Quest and PSVR already do this. It hardly has anything to do with system power, and is more about resolving contradictory sensor readings.

> But people watch 720p content all the time!

1) People don't tend to watch 720p content on large FOV displays.

For example, 720p on my phone is fine, because it takes up less FOV than a theater.

2) Content can be upscaled, picels cannot.

Resolution is only half the story. High bit rate 720p > Netflix levels of 4k video compression.

Downsampling compressed 4k video to 720p probably looks quite good as long as they don’t then compress the output.

Do you typically have issues with nausea?

It just seems to me like many people might struggle with VR on a plane given that planes and VR can each on their own cause people to vomit, and not only would you be using both at the same time, but they would actually impact each other because the plane has turbulence which would impact accelerometers but not cameras.

I have no idea how this would all work out in the end. Perhaps it wouldn't be as bad as one might think.

Like most technical advances throughout history, it likely won't be even close to nearly as bad as some people making a living suggesting it will be horrible.

No nausea issues with this setup for me at least. I'd say my VR stamina is probably average-ish? E.g. I use blink long-distance movement in Alyx and Red Matter because otherwise I get a bit dizzy, but otherwise my stamina is limited by headset comfort and battery.

Yeah the important thing is to turn off the cameras. It'd be a vomit inducer otherwise.

Yep. I have the NReal Air's.

I still prefer a TV when I'm chilling at home, but the NReals work great on planes.

Are they just for watching shows? (They look like they could be neat Linux glasses).

Piggybacking in case parent answers. I am confused why it works on a limited set of devices. Doesn’t it just need a video source? Can u plug it into a rPI?

The USB-c port you use them with needs to support video output. Not all USB-C ports support that.

I also have them working (without audio) with my Playstation.

The device needs to have a USB-c port with DP mode

Nope, they're essentially a general purpose portable monitor. They basically feel like a giant, 1080p projector screen. That's just in "dumb" mode.

* They supposedly work well with Dex (Samsung/Android VR space)

* They also have a desktop app called "Nebula" that can generate up to 3 virtual monitors. Resolution low for each monitor, but it's handy for having a bunch of different material in your view.

* They can also do 3D side-by-side mode.

I believe it just works as an external monitor. Games, web, coding - whatever you want

The NReals more comfortable, portable and rather less embarrassing than a full-blown headset like the Quest or Vision Pro as well, I imagine.

They're definitely more comfortable, but it's very clear your using some sort of VR device.

Yeah I have the Xreal Air as well and they are quite sharp at 49 PPD. Giving me a full 1080p resolution screen at 46 degree diagonal FPV which is nice.

The AVP is estimated to be around 35-42PPD.

A lot of VisionPro news that are appearing seems oblivious that the Quest 2 and that virtually it does everything VP does... that's typical of the Apple ecosystem I guess.

I’ve worn a Sony glasstron to watch movies on a planes, back in the Stone Age, and given that DVD at 480p was the pinnacle of quality at the time, it also worked just fine — as long as I didn’t move my head.

> The 6dof tracking is totally off because the cameras can't see the fact that you're moving and you just end up shifting wildly

Why? I don't get this. As long as the plane is moving at a constant speed it should be no different from sitting in a stationary room right? Unless there's like turbulence or something I guess?

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