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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Apple TV 4K

As long as you remember that 4k 60Hz 4:4:4 10 bit color doesn't fit in the bandwidth of a HDMI2.0x specification.
3840x2160x60x10x3>14.4 Gb/s
4:2:2 also looks pretty good.
 
I don’t have a specific link handy, but have also heard Apple streams 4K HDR in 8Mbps or less. I have a 12Mbps connection at my home (so frustrating) and have no trouble. Watched The Martian in 4K on AppleTV and it was vastly superior to the 1080p BluRay being upscaled locally. Playing at 4K is prioritized on the iTunes infrastructure so it seems to pre-cache on their end less. I experienced almost no buffering on my end, like less than 15 seconds and the movie played the whole way through without a hiccup. Doing comparisons, the streamed/downloaded 4K from AppleTV is 90% as good as proper 4K BluRays. Once again, where Apple/iTunes falls short is in the audio department.

Misha Engel said:
As long as you remember that 4k 60Hz 4:4:4 10 bit color doesn't fit in the bandwidth of a HDMI2.0x specification.
3840x2160x60x10x3>14.4 Gb/s
4:2:2 also looks pretty good.
Click to expand...

HDMI 2.0a, is 18Gbps, not 14.4Gbps.

3840x2160 @ 36bpc (3 x 12bit) x 60Hz is 17.9Gbps.

2160p @ 10bit 4:4:4 still leaves enough bandwidth for 32 audio channels @ 16bit 44KHz. Actually there’s just enough bandwidth for all that audio in 12bit 4:4:4, but it’s knocking on the door of 18Gbps and I don’t recall if all channels are supported there or not. After all, they’re a total combined of only 0.023Gbps. 0.03Gbps after packet overhead. 16 channels at 96KHz is also supported, but that pretty much never gets used.
 
Shitshow

Shitshow

Yes, it's a first world problem, that said: over compression by content providers is sabotaging the potential of higher resolution, dynamic range, color precision, etc. As if that wasn't frustrating enough, the display manufacturers have little incentive to improve their products just to make the macro-blocking and banding more prominent.

Jeers - #19
 
Jeff Kilgroe said:
I don’t have a specific link handy, but have also heard Apple streams 4K HDR in 8Mbps or less. I have a 12Mbps connection at my home (so frustrating) and have no trouble. Watched The Martian in 4K on AppleTV and it was vastly superior to the 1080p BluRay being upscaled locally. Playing at 4K is prioritized on the iTunes infrastructure so it seems to pre-cache on their end less. I experienced almost no buffering on my end, like less than 15 seconds and the movie played the whole way through without a hiccup. Doing comparisons, the streamed/downloaded 4K from AppleTV is 90% as good as proper 4K BluRays. Once again, where Apple/iTunes falls short is in the audio department.



HDMI 2.0a, is 18Gbps, not 14.4Gbps.

3840x2160 @ 36bpc (3 x 12bit) x 60Hz is 17.9Gbps.

2160p @ 10bit 4:4:4 still leaves enough bandwidth for 32 audio channels @ 16bit 44KHz. Actually there’s just enough bandwidth for all that audio in 12bit 4:4:4, but it’s knocking on the door of 18Gbps and I don’t recall if all channels are supported there or not. After all, they’re a total combined of only 0.023Gbps. 0.03Gbps after packet overhead. 16 channels at 96KHz is also supported, but that pretty much never gets used.
Click to expand...

Version 2.0

HDMI 2.0, referred to by some manufacturers as HDMI UHD, was released on September 4, 2013.

HDMI 2.0 increases the maximum TMDS clock to 600 MHz (18.0 Gbit/s). HDMI 2.0 uses 8b/10b encoding for video transmission like previous versions, giving it a maximum video bandwidth of 14.4 Gbit/s. This enables HDMI 2.0 to carry 4K video at 60 Hz with 24 bit/px color depth. Other features of HDMI 2.0 include support for the Rec. 2020 color space, up to 32 audio channels, up to 1536 kHz audio sample frequency, dual video streams to multiple users on the same screen, up to four audio streams, 4:2:0 chroma subsampling, 25 fps 3D formats, support for the 21:9 aspect ratio, dynamic synchronization of video and audio streams, the HE-AAC and DRA audio standards, improved 3D capability, and additional CEC functions.

HDMI 2.0a was released on April 8, 2015 and added support for High Dynamic Range (HDR) video with static metadata.

HDMI 2.0b was released March, 2016.[115] HDMI 2.0b initially supported the same HDR10 standard as HDMI 2.0a as specified in the CTA-861.3 specification. In December 2016 additional support for HDR Video transport was added to HDMI 2.0b in the recently released CTA-861-G specification which extends the static metadata signaling to include Hybrid Log-Gamma (HLG).
 
Blair S. Paulsen said:
The optical cables are pricey. Glad to hear Jeff has had good results with his copper HDMI cables from Sewell Direct, but be aware that many people I know have had headaches with copper over 3 meters. I wish you the best, but highly recommend you only buy from sellers who will replace or refund.

My setup is similar to Jeff's, though my AVR is an ARCAM 550. Never could get my DTV Genie to play nice above 1080. The OPPO 203 and Roku Ultra both do UHD/4K just fine. I should note that my Sony 600ES does not natively support HDCP 2.2 so I had to put an HD Fury Integral ($200ish) in line on the output side to get around it.

Cheers - #19
Click to expand...

I'm only going 15', so hoping the sewelldirect.com cables do the trick.
 
<-- currently using the Belkin cable, though I may be doing some weird audio stuff shortly that will require pass through. That will be an interesting adventure.
 
sure, the new 4K Apple TV has 444 colour and 4K movies from iTunes… but it fails at supporting 4K mkv converted H265 files. Big f___ time. I’ve been a an AppleTV fan and have owned all iteraations since it’s first incarnation. This is the first model that makes me want to abandon thier ecosystem.
 
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Jeff Kilgroe said:
HDMI 2.0a, is 18Gbps, not 14.4Gbps. 3840x2160 @ 36bpc (3 x 12bit) x 60Hz is 17.9Gbps. 2160p @ 10bit 4:4:4 still leaves enough bandwidth for 32 audio channels @ 16bit 44KHz. Actually there’s just enough bandwidth for all that audio in 12bit 4:4:4, but it’s knocking on the door of 18Gbps and I don’t recall if all channels are supported there or not.
Click to expand...
I watched an HDR film through an LG 4K Blu-ray player a few weeks ago, and the "info" button brought up a bandwidth display that revealed we were well over 50Mbps from Netflix (not nearly a gig). I believe the bandwidth on 4K Blu-ray can go all the way up to 120Mbps. To me, it looked fine and I didn't notice any artifacts, banding, glitches, or anything else. This is from Spectrum (formerly Crime-Warner) in Los Angeles.

Blair S. Paulsen said:
Yes, it's a first world problem, that said: over compression by content providers is sabotaging the potential of higher resolution, dynamic range, color precision, etc. As if that wasn't frustrating enough, the display manufacturers have little incentive to improve their products just to make the macro-blocking and banding more prominent.
Click to expand...
This is sadly true. I would love to see our video streaming bitrate increased, given that we've got 300Mbps from the local provider. Hell, even getting 100Mbps would be something. I wonder how much of this is Apple & Netflix & Amazon, and how much is Spectrum.
 
It's a complicated tale regarding internet bandwidth. I do think fairly soon we'll be getting to 1Gbps out here in LA LA Land, most of Spectrum tops out at 300Mbps down and 10-20Mbps up (weird that previous Time Warner is at 20 and previous Charter is at 10, they need to um... figure that out).

With 5G coming around the corner sometime within the next 2 years and likely floating in the 800Mbps-1Gbps range (with likely tiered services offered via throttling) it's going to be um.... odd if we can't have a hard line doing something as good.

Oddly enough the US average down is 70.75Mbps and upload is 27.64Mbps, with upload being slower than BOTH of Spectrum's offerings, but hey, I'm a content creator and have to deliver large files. I'm not everybody. This is slightly older data, but it's still not great.

What is good news is newer codecs like H.265 and VP9 have trimmed the bandwidth for decent looking 4K and 8K content, and there's been big improvements in optimization when it comes to encoding in the last 3-ish years, which is what you're seeing there Marc. It's going to be interesting to see how physical media competes shortly now that more affordable and likely more desirable Ultra HD Blu-ray players hit the market.

But yeah, faster internet please.
 
HEVC is VERY VERY processor intensive.

Apple will take the lead in streaming set-top streaming boxes for this reason, nobody has a set-top capable processor fast enough to decode H265. With today’s bandwidth in the US, to get the 4K with any quality, you NEED to stream H265. To decode H265 in that set top box, you need a super fast mobile processor.

Gee, think iPad Pro, iPhone X…… the AppleTV 4K uses a 64-bit A10X Fusion chip, same as in the iPad Pro.

This has been a well thought out strategy from Apple.

https://developer.apple.com/videos/play/wwdc2017/503/
 
From Apple's website


Video Formats

H.264/HEVC SDR video up to 2160p, 60 fps, Main/Main 10 profile

HEVC Dolby Vision (Profile 5)/HDR10 (Main 10 profile) up to 2160p

H.264 Baseline Profile level 3.0 or lower with AAC-LC audio up to 160 Kbps per channel, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

MPEG-4 video up to 2.5 Mbps, 640 by 480 pixels, 30 fps, Simple profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

Does this HVEC mean a special apple only proprietary High Efficiency Video Coding or is it the h.265 standard the rest of the world uses ?
Dolby states 10-bit HEVC: H.265 main10 profile does this mean Apple 4k TV does support h.265 ?

It's kind of weird, sometimes I capture 4,6k 60 fps at 8000 Mbit/s and the average "Joe the consumer" watches it at 4k 60 fps 16 Mbit/s and is freaking happy with the quality.
 
Marc Wielage said:
I watched an HDR film through an LG 4K Blu-ray player a few weeks ago, and the "info" button brought up a bandwidth display that revealed we were well over 50Mbps from Netflix (not nearly a gig). I believe the bandwidth on 4K Blu-ray can go all the way up to 120Mbps. To me, it looked fine and I didn't notice any artifacts, banding, glitches, or anything else. This is from Spectrum (formerly Crime-Warner) in Los Angeles.
Click to expand...

120Mbps, coded! To, say, HEVC.
Decode to RGB, and it's a completely different animal.
 
I would posit that the key issue is the approach taken by providers and distributors. They ask:

How small can we make the bitstream and still have "acceptable" quality?

Instead of:

What's the best quality we can deliver that the current infrastructure can handle?

They have been able to get by with such a strategy because very few consumers ever see a comparison between what they are being fed and something decent like ProResLT/DNxHD36 (I recognize that master quality is not a fair reference since it's too beefy to make it down the pipe). They are taking advantage of "you don't know, what you don't know" on the viewer's side. FWIW, display manufacturers and other links in the signal chain are more than happy to let the "bandwidth gatekeeper" dumb down the pipeline so they don't have to spend as much to reach expectations.

If I could, I'd go into people's homes and connect a proper source to one of the HDMI inputs on their display and toggle between their cable/satellite/IP feed and a master quality version of the same content. With a decent calibrated display and seating within 2 picture heights of the screen size, most folks with reasonably good eyesight would be stunned. Of course, in the real world, I can't visit millions of homes per day to run the comparo, but I'm starting to feel like that's the only way to get enough pushback from subscribers to have any impact on how the providers/distributors operate their concessions.

For now, I would guess that the vast majority of complaints/survey responses to distributors are about niche channels/pricing/bundling/etc - not picture quality. Until that changes, those of us who actually realize how much better it could be will continue to be too small a population to move the needle. If anyone has any strategies for changing that equation, I am all ears.

Cheers - #19
 
Blair Thornton said:
HEVC is VERY VERY processor intensive.

Apple will take the lead in streaming set-top streaming boxes for this reason, nobody has a set-top capable processor fast enough to decode H265. With today’s bandwidth in the US, to get the 4K with any quality, you NEED to stream H265. To decode H265 in that set top box, you need a super fast mobile processor.

Gee, think iPad Pro, iPhone X…… the AppleTV 4K uses a 64-bit A10X Fusion chip, same as in the iPad Pro.

This has been a well thought out strategy from Apple.

https://developer.apple.com/videos/play/wwdc2017/503/
Click to expand...

Apple is using PowerVR video decoder blocks and is still using some of the older PowerVR GPU IP that they licensed. They aren't using the CPU to decode video. They have incorporated some of their own hardware tweaks into the chipset - which is why they don't really say what they are using outright - that make it in line with their other hardware, as to make portability of apps between the various products and software development easier. The next upgrade should have a 100% Apple-designed GPU, though I can't see that happening unless Apple reinvents the wheel because GPUs are a patent minefield that requires an obscene amount of cross-licensing for features and hardware designs, though Apple can certainly afford to do so.
 
Jeff Kilgroe said:
Optical ones are expensive, if you are running 20’ or less, no need for optical. Even then, no issues if you have a properly powered source. Key Digital makes a great signal booster and repeater that supports full 4K with HDCP 2.2 if you need it.

I’m using these from Sewell Direct to feed my Sony 4K projector. And a second zone. No hiccups at all. Can run full 4K 60Hz 4:4:4 / Dolby Vision / HDR10. They are connected to the outputs on a Yamaha RX-A2070 receiver. My 4K sources are the new AppleTV, OPPO 203 and 4K HDMI 1.4 out of my DirecTV Genie. I have a RedRay player too, but it has never played nice with anything other than a few stand-alone 4K displays, so it doesn’t count for anything other than a deluxe door stop at this point.
Click to expand...

I ordered the same yet AppleTV 4K won't let me get 4:4:4 chroma or 60p HDR.

Using with a Sony XBR55X900E, which supports HDR10, like the AppleTV 4K. hmmm must be the setup on the TV.
 
Blair Thornton said:
I ordered the same yet AppleTV 4K won't let me get 4:4:4 chroma or 60p HDR.

Using with a Sony XBR55X900E, which supports HDR10, like the AppleTV 4K. hmmm must be the setup on the TV.
Click to expand...

Ofcourse it won't. No HDMI 2.0x interface can. Do the math (they did in Europe with 50p) and you will see it is simply not within the specs of HDMI 2.0x.
 
HDR will work on your setup, you may need to specifically enable the deep color and HDR settings for your input, depending on which firmware revision it can be disabled by default. Also be sure that it’s supported on the input you’re using on the TV. The X900E supports HDR on HDMI 2 and 3, not on HDMI 1.

As for 4:4:4 it’s not supported at 2160p 60Hz on the Apple TV. And generally speaking, Misha is correct that it is not supported by HDMI 2.0. HDMI 2.0a [and 2.0b] do support RGB and 4:4:4 at 10bit in unpacked stream mode. The open or unpacked stream mode is really for monitor only use, there is no HDR or other frame meta info and audio is not supported, it simply defines the signal parameters and blasts raw data. Essentially nobody is using open stream mode, not even desktop monitor makers as most people are using DisplayPort for monitor interfaces and keeping HDMI for AV components.

HDMI 2.0a and newer have added 4:2:2 support at 10bit. It was originally omitted for 10bit 50/60Hz and yet supported at 12bit 50/60Hz due to a few manufacturers citing bit alignment and packing issues that didn’t make sense and some other politically motivated crap. Sony was really the leader in that and I’m not sure what their motivation was. As they also led the charge to add the support in for 2.0a.

You should be able to do 10bit 4.2.2 HDR with your setup via the AppleTV. As the TV accepts RGB, 444, 422, 420 at 8 bit. 422, 420 at 10 and 12 bit. And 420 at 16 bit. AppleTV only supports 8bit and 10bit modes and should detect 10bit HDR support if you’re properly connected.
 
Its really shit that you cant download a 4k movie on apple tv 4k, as you do with hd. 4k is only streaming. I think apple should have put big warnings on the Apple TV box like it is on the cigarett boxen (in Sweden at least) where it it says smoking will kill you and harm all around you.
 
Yeah, it’s crap you can’t download in 4K. OTOH, any movie you currently own in HD thru Apple that becomes available in 4K can be streamed in 4K. AppleTV is OK for rentals... If I’m going to buy it, I’ll get the 4K BluRay for the slightly better picture (sometimes) and superior audio, multiple editions, often with digital so I still get it on iTunes/AppleTV anyway. At least that’s how it works here in the USA. Like The Martian to buy thru Apple is $24.99 and we get to download HD and it can be streamed in HD or 4K. I can buy it at WalMart or Amazon for $20 and I get the 4K BluRay, regular BluRay and the digital copy HD + 4K via Apple... Apple hasn’t quite figured out that their pricing sucks and that’s the reason they can’t crack that physical disc sales nut that keeps eluding them. OTOH, that $20 movie at WalMart is supposed to cost $35, they just choose to sell it at $20 and make $1 profit on each because they’ll sell 10 million of them.
 
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