HDMI-HDMI vs DVI-HDMI on nvidia ? - Page 2

Remicade · 23rd January 2015, 13:37

In the latest nvidia's drivers I can change between 16-235 and 0-255. Problem solved. I use 16-235.

Remicade · 25th January 2015, 20:00

Well it's wrong. If the source is PC I must choose 0-255 and if the source is a bluray player i must choose 16-235.

hello_hello · 25th January 2015, 22:13

Quote:

Originally Posted by Asmodian

Ah I see, yes they look the same.

Cheers.

Quote:

Originally Posted by Remicade

Well it's wrong. If the source is PC I must choose 0-255 and if the source is a bluray player i must choose 16-235.

Are you referring to the input levels you'd configure in the TV's setup? I'm not sure what you mean.

My TV (Samsung Plasma) lets me set the input level. The option's called "HDMI black level" (I think). "Normal" is PC levels and "Low" is TV levels. I can't remember if that applies to all the HDMI inputs, or only the dedicated HDMI/PC input. I'd need to check (the PC connected via HDMI isn't on at the moment), but the default would be TV levels and each HDMI input would be configured independently (as are most of the picture settings).

In the past (ie when using XP) the levels used by Windows itself were always full range. Therefore to get the TV to display Windows correctly, I set the TV to expect full range (PC) levels. I set the video card to expand the video levels to full range and video displays correctly also.

For newer Windows and drivers there's now two options. One sets the "global" levels (I think it's under Display Colours or something like that), so you can reduce Windows itself to limited range, connect to a TV expecting limited range levels, Windows would display correctly and no expansion of video levels is required (that's the levels option under the Video section).

Previously there was no "global" levels setting under "Display" and the drivers chose the global levels. That may have been the cause of your inability to change the "Video" levels previously and the reason for the "force full range" utility I linked to earlier. I don't fully understand that problem as I'm still using XP so it didn't effect me.

Anyway, I don't quite understand your "if the source is PC I must choose 0-255 and if the source is a bluray player i must choose 16-235" comment as the way I understand it this thread's only concerned with connecting a PC to a TV/Monitor so I'm not sure where Bluray comes into it.

Asmodian · 26th January 2015, 00:40

Quote:

Originally Posted by Remicade

Well it's wrong. If the source is PC I must choose 0-255 and if the source is a bluray player i must choose 16-235.

Why must you chose full range on the PC? What goes wrong if you do not?

If your TV is expecting limited set the PC to limited, if your TV is expecting full range set your PC to full. Full is naive for PC so if possible use full but it isn't wrong if you don't (finally).

Remicade · 26th January 2015, 05:57

Well I found this post in avs and I think it's right : "Never output anything other than RGB 0-255 from a PC source unless you have no other option. Everything other than video is rendered natively in the 0-255 range, so you are compressing levels to achieve a 16-235 output. Most video cards do not do this with especially high precision and will introduce banding into the image."

nvidia control panel it's a mistery for me: right now I'm stuck again at 16-235 I cannot change to 0-255 anymore. I give up

.

Ghitulescu · 26th January 2015, 10:22

Quote:

Originally Posted by Remicade

... right now I'm stuck again at 16-235 I cannot change to 0-255 anymore. I give up

.

Yes, the EDID is stronger than you

pandy · 26th January 2015, 12:02

0-255 is allowed only in DVI mode, for HDMI or 16-235/16-240 (limited quantization range) or 1-254 (full quantization range) is allowed.

Asmodian · 26th January 2015, 20:01

I do agree with that quote from avs but you seem to fall into the "unless you have no other option" category. You might as well do it correctly even if your display will not do optimally.

hello_hello · 26th January 2015, 22:02

Quote:

Originally Posted by pandy

0-255 is allowed only in DVI mode, for HDMI or 16-235/16-240 (limited quantization range) or 1-254 (full quantization range) is allowed.

But.....
The HDMI spec says YCbCr 4:4:4 or 4:2:2 can only be limited levels. My TV follows that rule. When the input is YCbCr the option to change the levels is greyed out. The Nvidia control panel on the other hand (keep in mind I'm running XP with older drivers) will still happily expand the video levels to full range even when the output is YCbCr.
To add to the fun, my TV will put itself intp "PC mode" when the right criteria are met, regardless of the input type (HDMI/PC input at 60Hz etc), so due to the "YCbCr always being limited" rule, PC mode can be limited levels. That seems counter-intuitive at first. For RGB, it lets you select what you want.

SeeMoreDigital · 26th January 2015, 22:13

Quote:

Originally Posted by Remicade

nvidia control panel it's a mistery for me: right now I'm stuck again at 16-235 I cannot change to 0-255 anymore. I give up

.

Out of interest, what options are under the 'Digital color format:' and 'Content type reported to the display:' options?

Cheers

hello_hello · 26th January 2015, 22:19

Quote:

Originally Posted by Remicade

nvidia control panel it's a mistery for me: right now I'm stuck again at 16-235 I cannot change to 0-255 anymore. I give up

.

I wonder if it's because it knows the TV is set to expect TV levels. If you change the TV setting to PC levels, maybe then the video card will let you select 0-255.

If that's the way it works it'd make sense, reducing the likelihood of mismatched levels. Whether it does or not I don't know. I'm using XP and old drivers that probably don't communicate that way and it doesn't work that way for me anyway, but maybe for newer windows versions.

I don't have the "report content type" option either. Apparently that can get the TV to switch modes. Maybe input levels too, or would that be silly? Probably.

SeeMoreDigital · 26th January 2015, 22:29

Quote:

Originally Posted by hello_hello

I wonder if it's because it knows the TV is set to expect TV levels. If you change the TV setting to PC levels, maybe then the video card will let you select 0-255.

Could well be... The HDMI communication protocols between devices can throw-up some weird results...

hello_hello · 26th January 2015, 22:40

Quote:

Originally Posted by SeeMoreDigital

Out of interest, what options are under the 'Digital color format:' and 'Content type reported to the display:' options?

I found an nvidia guide for a slightly older driver version, but for content type it says:

Auto select, Desktop programs, Full-screen videos, Photos, Movie, Games
Window Vista and later; Some HDMI displays only
- available values dependent on display support

Digital color format is RGB or YCbCr for HDMI and DisplayPort connections.

In my case when the connection is VGA the option disappears. Maybe the same thing happens for DVI but I'm not sure how Nvidia actually distinguish between HDMI and DVI. As I reported previously, my card only has DVI, but the control panels still shows the connection to my TV as being HDMI and it'll let me select either RGB or YCbCr.

hello_hello · 26th January 2015, 22:48

The content type option seems like something that'd have a fair potential to cause lots of "what's going on?".
http://forums.anandtech.com/showthread.php?t=2257420

nevcairiel · 26th January 2015, 23:10

Quote:

Originally Posted by hello_hello

The content type option seems like something that'd have a fair potential to cause lots of "what's going on?".
http://forums.anandtech.com/showthread.php?t=2257420

If left on "Auto", it can cause weirdness in some setups. Best to just set it to your main use-case, on my HTPC thats Video, and no problems.

That said, my current TV has never caused me any problems.

26th January 2015, 05:57	#25 \| Link
Remicade Registered User Join Date: Dec 2009 Location: Romania Posts: 98	Well I found this post in avs and I think it's right : "Never output anything other than RGB 0-255 from a PC source unless you have no other option. Everything other than video is rendered natively in the 0-255 range, so you are compressing levels to achieve a 16-235 output. Most video cards do not do this with especially high precision and will introduce banding into the image." nvidia control panel it's a mistery for me: right now I'm stuck again at 16-235 I cannot change to 0-255 anymore. I give up . Attached Images

23rd January 2015, 13:37	#21 \| Link
Remicade Registered User Join Date: Dec 2009 Location: Romania Posts: 98	In the latest nvidia's drivers I can change between 16-235 and 0-255. Problem solved. I use 16-235.

25th January 2015, 20:00	#22 \| Link
Remicade Registered User Join Date: Dec 2009 Location: Romania Posts: 98	Well it's wrong. If the source is PC I must choose 0-255 and if the source is a bluray player i must choose 16-235.

26th January 2015, 12:02	#27 \| Link
pandy Registered User Join Date: Mar 2006 Posts: 1,049	0-255 is allowed only in DVI mode, for HDMI or 16-235/16-240 (limited quantization range) or 1-254 (full quantization range) is allowed.

26th January 2015, 20:01	#28 \| Link
Asmodian Registered User Join Date: Feb 2002 Location: San Jose, California Posts: 4,407	I do agree with that quote from avs but you seem to fall into the "unless you have no other option" category. You might as well do it correctly even if your display will not do optimally.

26th January 2015, 22:48	#34 \| Link
hello_hello Registered User Join Date: Mar 2011 Posts: 4,829	The content type option seems like something that'd have a fair potential to cause lots of "what's going on?". http://forums.anandtech.com/showthread.php?t=2257420