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Comment by bscphil | Hacker News Reader

> 4K!

I'm very excited about these upgrades too (especially GigE), but as far as I can tell nothing on this news page specifies whether the Pi will also support HDR output as part of the 4K upgrade. That's most of the practical benefit of 4K - that 4K releases tend to come with HDR10 or DolbyVision support.

Anyone know if we can expect HDR output to work? If I knew it supported that I'd be purchasing one right now to upgrade my media center from my current Pi 3 setup.

Even the tech specs page says nothing about 10bit decoding, which is required for most real world 4K HEVC video.

> H.265 (4kp60 decode), H264 (1080p60 decode, 1080p30 encode)

https://www.raspberrypi.org/products/raspberry-pi-4-model-b/...

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From Libreelec article on RPI4:

"The 4B hardware is HDR capable, but software support has a dependency on the new Linux kernel frameworks merged by Intel developers (with help from Team LibreELEC/Kodi) in Linux 5.2 and a kernel bump will be needed to use them. Once the initial excitement and activity from the 4B launch calms down, serious work on HDR and transitioning Raspberry Pi over to the new GBM/V4L2 video pipeline can start."

Full article: https://libreelec.tv/2019/06/libreelec-9-2-alpha1-rpi4b/

The Raspberry Pi 4 B uses ARM VideoCore IV. As far as I can find HDR will only come in the updoming VideoCore V. So no. No HDR yet.

That's really too bad. It makes the 4K support useless for building an HTPC, which is a common use for the Pi. As far as I can determine, several of their competitors already support 10bit decoding, although specifics (about stable HDR support) are sometimes hard to come by.

As a fifty seven year old, I don't have 4k eyeballs. agree you have a limitation, not one which is holding me back since osmc does 720p just fine, for Olde telecine mp4s of B&W movies

If the screen is large enough about everyone gets 4k eyeballs.

I have a 4K-capable 40 inch TV in a standard living room (for Europe). 4K videos look slightly crispier than full HD ones.

While I could have a slightly larger TV, I think that for typical domestic use 4K's improvement is marginal because people are not sitting 50cm from the screen and room sizes are limited.

Really, so far the top benefit has been that I could tell my wife: "Look, if I move right up to the screen I can still see Jeremy Clarkson's individual hair strands!"

A 40 inch TV is on the small end for 4K having any real benefit (at least at a normal living room viewing distance).

I'm still struggling a bit with large screens. For something like playing games I'm guessing you can comfortably sit back. High resolution screens for computers feel attractive, but getting up close and personal can feel a bit much with light levels. I'm guessing OLED might be nicer in that regard.

For those of us who aren't there, can you clarify how big a standard European living room is? This has nothing to do with the resolution stuff you mentioned, just curious.

In the UK in a victorian terrace, and our front room is perhaps on the small side at about 3x4m. I'd guess somewhere between that and 4x5m is about average. For us 32inch still can feel imposing. And that size screen seems to be being phased out.

Oh dear God that's tiny. How do you stand that? Genuinely curious; I feel like I'd end up claustrophobic.

We do have another room, that's slightly larger but it's a bit bleak. And weirdly it's a more fussy room to furnish. The smaller size is better in the winter. The old brick terraces aren't that warm. In large houses people can gravitate to smaller rooms for that reason. Personally I'd like a large room that I could bring the furniture in from the sides. Lucky to even have a house to live in to be honest, so can't really grumble.

I looked up some pictures; would you say this is representative? https://img-new.cgtrader.com/items/969757/41efc6817b/modern-...

If so, you're right; that's pretty small. Is it just a matter of acclimation?

Also, can you clarify what you mean that you're lucky to have a house? I wasn't aware of a major homeless problem in Europe.

I have to comment. That's huge! Way bigger than most UK Victorian 2 up, 2 down terraces. More like the size expected in an older 4 bedroom house if you ignore the extra space the photographer is clearly standing in.

Have a random right move link of what I think as typical Victorian worker's terrace: https://www.rightmove.co.uk/property-for-sale/property-62228...

The door by the yellow chair is a tiny porch with front door beyond. No idea how it compares with OP's.

That's slightly smaller than ours probably all in all. But I've seen smaller, like the one up, one down back to backs in Leeds/Woodhouse and many modern flats apartments, are just broom cupboards - but then you look at down town Japan and this feels palacial.

That's larger than mine. Sizes are getting smaller. Can't comment for the rest of Europe but the UK has quite a bad homeless problem, it's very visible at the moment. Rents are prohibitively high, and getting onto the housing ladder is very difficult. Small houses - even semi-detached bungalows around our way are at least £300k (edit: oops missed a 0 originally!). The housing stock is shockingly bad in the UK, and very expensive.

> I wasn't aware of a major homeless problem in Europe.

Homes in the UK can be expensive, so there's a large rental market.

On top of that many people are vulnerably housed - living in emergency temporary accommodation (which may be for many months) or on friend's sofas.

The introduction of the benefit "Universal Credit" has increased homelessness and people who are vulnerably housed. In the UK a landlord can apply for eviction if the tenant hasn't paid for two months. (This is for shorthold tenancy agreements where tenants have most rights - other tenancies have less protection.) There is a minimum wait of 5 weeks before Universal Credit claimants get paid, which pushes some people very close to this limit. The bizarre sanctions regime tips many people over that limit.

Detailed information can be found here:https://www.crisis.org.uk/media/238700/homelessness_monitor_...

I'm sure most of humanity for most of history have made do with smaller rooms than that.

How do you cope in a car?

Sounds like a car might just be bigger...

But joking aside, I'm surrounded by glass on all sides in a car. That makes a great deal of difference. I probably wouldn't feel confined in a room that size if I had an entire wall of glass.

In a UK terrace, even given a large bay window, your view will likely be squandered by a large work van, as the terraces seldom have off-street parking.

I've got a 4K TV and it's placed in a location that I can tell whether or not something is 4K if I sit a bit closer, but the core problem is that it's still very difficult to provide it true 4K content, since I've not been willing to drop the money for 4K blurays.

I've got a variety of content that is, technically, a video stream that decodes into a framebuffer that is a "4K" framebuffer according to the metadata on the video, but without enough bits for it to truly be "4K"; the same number of bits dedicated to a 1080P video would look just as good.

For all the bragging about how streaming is the future, it seems to me that the companies providing those streams at scale still have a lot of incentive to cut the bitrate back so far that it's not practically a 4K stream anymore, because 95%+ of their audience can't really tell.

I'm in my 50s as well and may eyes are definitely showing their age, but if anything I find high fidelity screens more important to me now than they were years ago. I use 1080p 23" screens at work and the slight blurriness from pixelation is definitely noticeable. Comparatively, the 5k screen on my iMac is dramatically sharper and easier on my eyes.

I find that when my own vision is slightly blurred, add in even more slight blurring on the screen and they compound each other. On the other hand if the source image is pin sharp, it makes it easier to cope with the flaws in my own vision.

> I don't have 4k eyeballs.

I'm sure higher resolution is nice, but nowadays I'm more interested in HDR and larger colour gamuts (Rec.2020).

I don't doubt 4K and 8K look "better", but IMHO we're approaching the point of diminishing returns, and visual enhancements in other areas are worth exploring (even for 1080p).

I suppose a future AV improvement will be to upgrade eyeballs; iSpheres anyone?

Yeah, with DRM that blanks out copyrighted content you haven't paid to watch, and reinserts adverts that your adblocker removed.

And they'll remove the optic nerve connector in favour of Bluetooth that will allow them to be 0.1mm thinner, and be wireless!

Ps did you miss iBalls on purpose?

I think Apple would go with iSpheres, it sounds more expensive.

I know we're talking video here but I wanted to share something. My father just got a new set of 'ears', he's been going deaf. They are titanium studs that are implanted into the bone just behind the ear, about the size of pencil erasers. They work through bone conduction. The hearing part are replaceable electronics that snap on and off the studs.

The current gen are about the size of a quarter and are bluetooth capable, so he can sync to his devices, watch movies, etc with these little guys tucked behind some hair.

It got me thinking, I wonder if audio guys have started to look at some of this sort of thing to really "hear" music perfectly. Very interesting tech.

There are some earphones that use bone conductance, but this sounds like a special case.

If hearing is down to tiny hairs in your ear resonating with the audio frequency, I would have thought being hard of hearing was down to those hairs not being able to function properly. How does bone conductance audio get around that? Does it use a different sense?

My eyesight is also going, I have to rub my eyeball on the phone screen like one of those anti-deorderant balls, I daresay my hearing will be next.

homo cyberia

(That's probably nonsensical latin, if anyone with a modicum of latin knowledge wants to go all Life of Brian on it, please feel free. What is latin for augmented human?)

iBalls tyvm

I'm not sure I'd use a pi has an HTPC for true blue-ray type 4K. Not to ding it, and I'm very excited (and happy to be proven wrong), but I'm not sure it will have the performance for that. I expect quite a bit will depend on whether or not someone puts in the software optimization work, as I remember how powerful PCs couldn't decode what they can on today's codecs a few years back. But we'll see.

I guess maybe if you added a heatsink and/or fan? I'd be a bit concerned about component life, taxing it that hard.

Oh yeah, and I wanna see how this thing overclocks.

> That's really too bad.

You people are never happy, aren't you? You're still getting more stuff for basically the same price...

The spec table says VideoCore VI. I really hope that is not a typo. I suspect it really is a VC6 because 2x4k is a big bump in pixel count and without a corresponding bump in fill-rate, perceived performance will drop.

[edit] looking at the benchmarks it's a modest boost. Now about twice the FPS of a PI-2 for Quake3 at equal resolution. Be interesting to see if something with more complex shaders changes the relative performance.

The VideoCore 4 (fuck the roman numerals, for exactly this reason) can not output 4k and it is also not a ES 3.0 capable GPU. So this must be a 5 or 6.

I'm crossing my fingers here. This is really something they should have put in the specs if it's supported. With 10bit decoding and Rec. 2100 [1] support, this would make a fantastic platform to build a media center on. I'd certainly upgrade from the Pi 3 even though I don't currently have a 4K television.

[1] https://en.wikipedia.org/wiki/Rec._2100

I looked at the dmesg from someones Phoronix testsuite run and it has:

[drm] Initialized v3d 1.0.0 20180419 for fec00000.v3d on minor 0

So this is vc5/6, not vc4. Additionally:

    Vendor: Broadcom (0x14e4)
    Device: V3D 4.2 (0xffffffff)

Do we know for sure that all VC5/6 SoCs support HDR decoding, or is that still unknown? The Wikipedia page for VideoCore only lists one VC5 SoC and no VC6 SoCs. The Broadcom page for the VC5 SoC is pretty uninformative.

Edit: I found this thing someone on the RaspPi forums put together! https://cdn.shopify.com/s/files/1/1560/1473/files/Inside_Ras...

> The Pi 4 has seen an upgrade to VideoCore VI.

> The H.265 / HEVC decoder is a HEVCv2 Main 4:4:4 10 design supporting bitstreams up to profile 5.1

Sounds promising! (The documentation on the website should certainly be fixed if this is correct.) Now assuming Rec. 2100 is properly supported to allow connecting to HDR capable displays over HDMI 2.0, we should be good!

> Sounds promising! (The documentation on the website should certainly be fixed if this is correct.) Now assuming Rec. 2100 is properly supported to allow connecting to HDR capable displays over HDMI 2.0, we should be good!

As hopeful as I am, that's quite a big assumption...

The KMS in this new chip is still the old VC4 HVS (high-speed video scaler). That chip can not output any 10 bit formats.

(But it also wasn't capable of 4k60, so maybe there are some modifications there.)

This was mentioned in the rpi forum by staff:

    May I ask whether RPI supports things such as 10 bit video decoding, Dolby Vision and Atmos? Thx.

HEVC hardware decode supports 4kp60, 10-bit. Audio output is pretty much unchanged, but the HDMI audio channels now support 8x192kHz bitrates.

Sure, but the video decode IP is a different piece of hardware from the video scaler/compositor. In a typical SoC, you have the GPU and the video decode engines as separate blocks that feed into the video scaler/compositor which then blends, rotates, scales, .. etc the inputs and feeds the final signal to LVDS, HDMI or whatever.

Now does it make sense to have your video decoder support 10 bit when your compositor can't handle that format? I guess you could argue that 10 bit source material will still improve the quality even if you downsample it to 8 bit for display, and I think for example DVB-T2 has standardized on 10 bit so if you can't decode that, that's a large chunk of market gone.

Ultimately, from the little we know, the compositor hardware is the same as the old Rpi, and that couldn't do 4k60 and it can't do 10 bit depths. The Raspbian image currently doesn't use the Linux kernel implementation for driving the compositor (it uses the fkms or "firmware kernel mode setting") so there might well have been hardware tweaks.

(Ok, instead of making this comment thread any longer, I simply asked and the compositor hardware in the RPi indeed has HDR support:

https://github.com/raspberrypi/linux/issues/3020#issuecommen...

Tweaked from the old HVS in the old RPis.)

Yeah, that makes sense - you wouldn't want to gimp the system by only doing half a job :)

What are the odds that this will support 1080p streaming with Plex? I've tried Plex on a Pi 3 using a Roku as a player with 1080p and it's a complete failure. Plex tries to encode everything even if native playback to the Roku is possible using the Roku media player.

My plex isn't on a Pi but I do not have this issue with Roku Express as a player. Could be other factors like the video codec and direct stream is set on Roku.

If encoding is required? Almost certainly won't work, it's just not powerful enough. But you should avoid reencoding if at all possible, and I imagine it will work if you can manage to disable it.

VI == 6 IV == 4

6 IV is 24

I haven't been able to get HDR working on my desktop amdgpu + X11. I don't think it's supported in Wayland yet either (let me know if I'm wrong) and the devs in #mpv on freenode said they don't have HDR10 output support either (although mpv can do HDR10 tone-mapping).

For HDR videos, I still play them via my Windows box. I think the current MacOS supports HDR too (and if not, it will get support soon as they have that crazy new $6k HDR screen).

don't want to derail the RPi4 celebration, but for this specific purpose (media centre) I've been super happy with Nvidia Shield. You can often pick them up for $150 on a sale, less on ebay. 4k HDR, runs Android TV (some people have managed to get Ubuntu running on it too), VLC/Kodi work well, Moonlight works well for game streaming from another gaming PC with NVidia card. It's super zippy, too, and quite small (though bigger than RPi).

Can you stream from a local media source, e.g. SMB share?

yep

Yeah, the Shield seems to be the standard here. If we can get confirmation that the Pi works, we'll have an alternative that is much cheaper and is more useful as a general purpose platform!

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