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View Full Version : HDMI RGB instead of YPbPr


Lee Bailey
02-17-09, 03:23 PM
This is probably beating a dead horse, but why does the VIP722 only support RGB color and not YPbPr?

When I online chatted with Dish, the person on the other end's answer was that RGB and YPbPr are cable formats.:nono2: HDMI is considered to be an RGB cable, so that's why they send RGB.:nono2:

I had to explain that RGB and YPbPr are also used for color spaces, and that my Blu-Ray player offers the option. In which the reply was simply, you can't switch to YPbPr on the VIP722.

Any other opinions on this issue?

renpar61
02-17-09, 03:57 PM
I'm by no means an expert nor technician, so my answer could be off. But as far as I understand it, RGB and YPbPr refer to color decoding. HDMI standard should support both, it just depends on how it's implemented on the source (ViP722 in this case).
Please correct me if I'm wrong.

BattleZone
02-17-09, 04:19 PM
I'm by no means an expert nor technician, so my answer could be off. But as far as I understand it, RGB and YPbPr refer to color decoding. HDMI standard should support both, it just depends on how it's implemented on the source (ViP722 in this case).
Please correct me if I'm wrong.

You are correct.

RGB and YPbPr are two ways of sending video across 3 coax lines, and there are digital equivalents that are options for HDMI.

But the answer is that most home consumer electronics equipment that use component use the RGB format, so it makes sense to support that. Sat companies purposely limit the number of user options, because everytime a customer is given an option, 10% will screw it up and then call in to complain. As it is, there's a huge number of HD customers whose receivers are set to output at 480i, and they don't know any better. And when those customers find out that they've been missing HD, they blame the sat company, not themselves for not adjusting the setting.

There's very, very little benefit for supporting YPbPr vs. RGB, yet plenty of potential for hardware incompatbilities, so it just isn't done.

The PS3 is designed to be a higher-end piece of equipment, and is marketed very differently, so it has all kinds of features that you won't find in a sat receiver.

smackman
02-17-09, 04:21 PM
I'm by no means an expert nor technician, so my answer could be off. But as far as I understand it, RGB and YPbPr refer to color decoding. HDMI standard should support both, it just depends on how it's implemented on the source (ViP722 in this case).
Please correct me if I'm wrong.

I believe you are correct. My Television HDMI Input does not accept both. The HDMI output from my 722 washes out my my Mitsubishi picture so I use component.
Something to do with PC inputs levels; 0-255 color spacing and 16-255 color spacing.
Over my head but I know its a issue with some Televisions.

renpar61
02-17-09, 08:47 PM
:icon_da:

4HiMarks
02-18-09, 07:46 AM
I think SaltiDawg is right, although I'm by no means an expert either. IIRC YPbPr is commonly referred to as "component video" and the 722 does support it.

smackman
02-18-09, 08:45 AM
I think SaltiDawg is right, although I'm by no means an expert either. IIRC YPbPr is commonly referred to as "component video" and the 722 does support it.
Thru component connection not HDMI.
HDMI is RGB only.



Here is a explanation from what I consider to be a expert in the field. This article concerned certain Mitsubishi Televisions and HDMI Inputs;

There are two luma standards for DVI / HDMI. Both have 0~255 levels of luma.

The first standard is call VIDEO luma, or CE luma, and uses level 16 for black and level 235 for white. This provides for levels 0~15 to be blacker than black (BTB) and for levels 236~255 to be white than white (WTW).

The second standard is called PC luma and uses level zero for black and level 255 for white. This is the standard that Mits used.

Mits didn't really make an error because different types of boxes are using either standard. Many BluRay players can be switched between either standard. All HD-DVD players use PC as well. And some satellite boxes use PC, but they are rare.

If you connect a source to the HDMI that uses PC luma then the calibration will be perfect through HDMI. However, if you have a source that uses VIDEO luma the blacks will be too bright and washed out, and the whites won't be bright enough, and the gamma will be all messed up.

If you connect a BluRay, look in the user menu for a setting for this. It is confusing because only Sony seems to label it properly as 0-255 / 16-235. All other manufacturers have used cryptic names such as "lighter"/"darker", or enhanced/standard...

Also, I think the HDMI on the xxx15's might accept YCbCr as well. If your BluRay has this option, try it and see how it compares to RGB 0-255.

Lee Bailey
02-18-09, 10:39 AM
Yes. That you and the CSR are confused.

The 722 has a Component out (Y Pr Pb) as well as an HDMI out. Both for TV1.

You're correct, the terminology should be YCbCr or RGB. HDMI supports them both. The VIP722 should negotiate with the HDMI connected device and set it appropriately, but it apparently does not.

This also might explain why my black levels are not the same between Blu-Ray and the VIP722. I have to set my TV's HDMI connection from the VIP722 black level to Low to get them darker.

Here's an interesting article about it:

HDMI - video levels and color space (http://www.hdtvmagazine.com/forum/viewtopic.php?t=5317)

ZBoomer
02-18-09, 09:05 PM
There is a place in the menus to set color space to RGB or Y Cb Cr, but it has been grayed out as long as I can remember. No idea why.

There are also options for Reset HDMI, HDMI on/off, and HDCP enable, which are also grayed out. Too bad, I'd love to play with these options.

Anyone know if these were ever available?

(Menu 6, 3, analysis, HDMI Test)

smackman
02-18-09, 09:19 PM
There is a place in the menus to set color space to RGB or Y Cb Cr, but it has been grayed out as long as I can remember. No idea why.

There are also options for Reset HDMI, HDMI on/off, and HDCP enable, which are also grayed out. Too bad, I'd love to play with these options.

Anyone know if these were ever available?

(Menu 6, 3, analysis, HDMI Test)

In Oct. 2007 I was part of a Beta Test for Dish where this color space option was not grayed out. I was able to choose between RGB and Y Cb Cr. When I chose Y Cb Cr, My picture on my Mitsubishi WS-55517 was awesome using the HDMI Output. 6 weeks later the beta test ended and Dish told me it would probably not be to Dish's best interest to offer such a switch .
I currently use component and have a excellent picture with deep blacks.

GiBi
02-19-09, 08:44 PM
In Oct. 2007 I was part of a Beta Test for Dish where this color space option was not grayed out. I was able to choose between RGB and Y Cb Cr. When I chose Y Cb Cr, My picture on my Mitsubishi WS-55517 was awesome using the HDMI Output. 6 weeks later the beta test ended and Dish told me it would probably not be to Dish's best interest to offer such a switch .
I currently use component and have a excellent picture with deep blacks.

My TV also benefits from setting YCbCr rather than RGB and would like to have this option. Has anyone ever tried contacting Dish asking them if they're ever going to re-enable that option again?

jkxmlr
03-09-09, 08:46 PM
"But the answer is that most home consumer electronics equipment that use component use the RGB format, so it makes sense to support that. Sat companies purposely limit the number of user options, because everytime a customer is given an option, 10% will screw it up and then call in to complain. As it is, there's a huge number of HD customers whose receivers are set to output at 480i, and they don't know any better. And when those customers find out that they've been missing HD, they blame the sat company, not themselves for not adjusting the setting."

And yet they believe the "professional" installer who tells them their RPTV from Jan 07 is not HD capable. And yet he sets the output from the 622 HD Receiver he is getting paid to install to 480P. A least he sold them a $50 HDMI cable. All this and leaving them doubting their purchase. Yes the consumer should educate themselves. But anyone who works in a position with interaction between the enduser and the technology they are installing, should take the time to learn what they are talking about, or bone up and say they are not sure. People tend to believe those who are in the position to be deemed knowledgeable.