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Yes, its set to output full RGB by default.

(Also, if you have to ask for that..
Do a 10 point greyscale reading. Look at the brightness graph. Switch the setting on your TV. Repeat. Look at the brightness graph. ;) Chances are, you can even do it in one set of readings. ;) )

In your calibration software use 16-235 colors, they will get auto converted afair (but it has been close too a year that I used it last - so please correct me if I'm wrong (small chance ;) )).
Thanks. The only reason I ask is that I swear when I first started using it, when booting the Pi it would present a test pattern window whereas the latest version boots to a black screen, which threw me for a bit. Haven't had a chance to dig any deeper, but of course it would have been obvious just changing the TV settings as well. Doh.
 

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Don't worry, just pointing out, that that is a fairly simple way to check it in general. :)
If I'm doing measurements, thats one of the first checks I do in the process to see if I've forgotten to set up the signal chain correctly. ;) Its less rigorous than to go through checklists, so its easier to simply keep it as a step in there. Its also less tedious than going for video black bar patterns, if you know what you are looking for.


All of that is - its easy, if you know what color ranges to feed the signal generator in the first place - or if you own an OLED, which makes it fairly trivial to understand what black and 16 IRE grey is. ;)

So for Pi PGenerator:
- Input signal range (of your calibration software) should be limited (it will do the signal conversion on its own)
- Output is always RGB Full by default
- So your TV has to be set to expect full signal range ("High black level" in LGs wording)
 

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Don't worry, just pointing out, that that is a fairly simple way to check it in general. :)
If I'm doing measurements, thats one of the first checks I do in the process to see if I've forgotten to set up the signal chain correctly. ;) Its less rigorous than to go through checklists, so its easier to simply keep it as a step in there. Its also less tedious than going for video black bar patterns, if you know what you are looking for.


All of that is - its easy, if you know what color ranges to feed the signal generator in the first place - or if you own an OLED, which makes it fairly trivial to understand what black and 16 IRE grey is. ;)

So for Pi PGenerator:
- Input signal range (of your calibration software) should be limited (it will do the signal conversion on its own)
- Output is always RGB Full by default
- So your TV has to be set to expect full signal range ("High black level" in LGs wording)
Thanks. The odd thing is I had no issues calibrating using the same set-up a few months back, and the only thing that has changed is I updated PGenerator. I'm wondering now if there is an issue with my meter.
 

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I doubt it. (If you are using a colorimeter, those are usually pretty stable. (within reason)) Describe the issue. :)

Welcome to calibration, btw. ;) (Potential error source everywhere. ;) )
 

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Is there a thread that covers how to get a PGenerator box up and running and it's details? Do you have to build your own? Can it produce an HDR10 signal?
 

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Discussion Starter #526
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Thank you!

Two more questions:
1) what's the cheapest HD Fury device that can inject metadata? There's a $80 Dr. HDMI device, but can that inject HDR metadata?
2) I'm just getting started with display calibration for my home TV sets as an enthusiast. Probably going to start with an HCFR + X-Rite i1 Display Pro + Tim's Ted's Disc Media Files setup. Will AppleTV 4K's signal processing errors you've identified truly render a calibration with that setup ineffective? Or is the point of bit-perfect only for professionals and/or calibrating the colorimeter?
 

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Discussion Starter #528
You are welcome.

1) HD Linker
2) Who's Tim? :). IMHO, accuracy has no levels. You have it or you don't, ATV4K is not bit accurate or at least that is what DVDO Analyzer told me, still if someone with better/more capable hardware could test it, I'd be glad. RPi PGenerator is the best cheap solution so far.
 

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Discussion Starter #529
Here we go, again. ;)

02.28.2020 UPDATE

it'll be a quick update! I did some testing on an Apple TV FullHD (4th Generation) and an Amazon Fire TV Stick 4K:

- Apple TV Full HD is bit accurate only with RGB output. YCC is not accurate with YCC content or if used as TPG.

- Amazon Fire TV Stick 4K has YCC output bit accurate but can't be used as TPG because I tried with LS Connect and I didn't get bit accurate results.

So, we can use Apple TV Full HD as TPG only with RGB output, while Amazon Fire TV Stick 4K can't be used as an accurate TPG at all.

First post has been updated too.
 

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Here we go, again. ;)



02.28.2020 UPDATE



it'll be a quick update! I did some testing on an Apple TV FullHD (4th Generation) and an Amazon Fire TV Stick 4K:



- Apple TV Full HD is bit accurate only with RGB output. YCC is not accurate with YCC content or if used as TPG.



- Amazon Fire TV Stick 4K has YCC output bit accurate but can't be used as TPG because I tried with LS Connect and I didn't get bit accurate results.



So, we can use Apple TV Full HD as TPG only with RGB output, while Amazon Fire TV Stick 4K can't be used as an accurate TPG at all.



First post has been updated too.
Is Apple TV fullhd different from the Apple TV 4k?

So this means we shouldn't set the Apple TV to YCC for content watching?
Sent from my Pixel 4 XL using Tapatalk
 

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Discussion Starter #531
Yes, they are different. 4K is capable of 2160p and HDR, while Full HD (4th gen) is limited to 1080p SDR.

YCC errors are not huge (from 0 to max 3 digital errors), you won’t notice them with real content.
 

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Yes, they are different. 4K is capable of 2160p and HDR, while Full HD (4th gen) is limited to 1080p SDR.



YCC errors are not huge (from 0 to max 3 digital errors), you won’t notice them with real content.
So is the 4k also RGB bit perfect like the Full HD?

Sent from my Pixel 4 XL using Tapatalk
 

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Discussion Starter #533
From the first page:
“ The Apple TV 4K, in fact, with output YCbCr and RGB seems to process the image continuously returning fluctuating values with digital errors ranging from a theoretical minimum of 1 to a theoretical maximum of 6 per triplet (as shown in the chart in which Ted patterns are used). For this reason, even if I reported the minimum values (by looking for them pixel by pixel) I did not calculate the relative dE for a simple reason: Apple TV 4K is not effectively usable as a TPG. That's why I will not proceed to test it further.”
 

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- Amazon Fire TV Stick 4K has YCC output bit accurate but can't be used as TPG because I tried with LS Connect and I didn't get bit accurate results.
Can I ask how you verified that the Fire TV Stick 4K is bit-accurate with YCC output? Was this playing a media file, and if so, with which media player?
 

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Discussion Starter #535
As described in the first post, I use the analyzer feature of my DVDO AvLab TPG. I used VLC and MrMMc app displaying Ted’s patterns.
 
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From the first page:

“ The Apple TV 4K, in fact, with output YCbCr and RGB seems to process the image continuously returning fluctuating values with digital errors ranging from a theoretical minimum of 1 to a theoretical maximum of 6 per triplet (as shown in the chart in which Ted patterns are used). For this reason, even if I reported the minimum values (by looking for them pixel by pixel) I did not calculate the relative dE for a simple reason: Apple TV 4K is not effectively usable as a TPG. That's why I will not proceed to test it further.”
Thanks I saw that, but I thought maybe with updates that it could improve and potentially get fixed.

Sent from my Pixel 4 XL using Tapatalk
 

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Is it just that Apple doesn't give a ***** or that they don't know about it or that they don't know how to fix it. Either way that is unacceptable on Apple's part, 99% of applications are going to use it in YCbCr not RGB.
 

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From the first page:
“ The Apple TV 4K, in fact, with output YCbCr and RGB seems to process the image continuously returning fluctuating values with digital errors ranging from a theoretical minimum of 1 to a theoretical maximum of 6 per triplet (as shown in the chart in which Ted patterns are used). For this reason, even if I reported the minimum values (by looking for them pixel by pixel) I did not calculate the relative dE for a simple reason: Apple TV 4K is not effectively usable as a TPG. That's why I will not proceed to test it further.”
Hello,

Apple TV 4K has some known issues with Match Frame Rate turned on, it can cause flashing, particularly at low light levels. Did you test with match frame rate on or off?

Could you tell me what native frame rate the patterns generated by LightSpace Connect are?

Many thanks
 

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I tested it today with 1080p sdr ycbcr 4:4:4 and rgb high with 24p.

With both color and framerate matching on or of there are triplet fluctuations.

I’ve used ted’s patterns with mrmc app.
 

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Discussion Starter #540
Hello,

Apple TV 4K has some known issues with Match Frame Rate turned on, it can cause flashing, particularly at low light levels. Did you test with match frame rate on or off?

Could you tell me what native frame rate the patterns generated by LightSpace Connect are?

Many thanks
With my chain, what causes low light scene/pattern flashing is using ATV 4K at 4K resolution with and without adapt frame rate. What makes it to stop is using 1080p with or without adapt frame rate.
 
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