4th generation Core graphics : no deep color ?

[CQuar]

As CustomModeApp.exe interface for custom Iris Graphics resolution is limited to 32bpp, I am now wondering whether the 4th gen Core graphics is capable of 10bpc for a static image at full resolution, at least for HDMI , DisplayPort / ThunderBolt output.

I read in Vol 1 datasheet section 2.5.1 :

"Processor Graphics VGA Registers

The 2D registers consists of original VGA registers and others to support graphics

modes that have color depths, resolutions, and hardware acceleration features that go

beyond the original VGA standard."

yet section 2.7 says : "Intel FDI supports 8 bits per color only.

Intel FDI is not encrypted as it drives only VGA and content protection is not

supported on VGA."

It is not clear to me how a VGA signal could be extracted without going via FDI.

Section 2.6 describes the wonderful sink :

The HDMI* interface supports HDMI with 3D, 4K, Deep Color, and x.v.Color. The

DisplayPort* interface supports the VESA DisplayPort* Standard Version 1,

Revision 2.

It is not clear to me whether with 4 lanes the source would be capable of configuring, sending through pipeline, transcoding a deep color signal to DPAux, DDI ports B, C or D.

Also if 32bpp can be conveyed (8 bits red, 8 bits green, 8 bits blue, 8 bits transparency), is there any way to convey 10 bits red, 10 bits green , 10 bits blue and forget the transparency ?

What sections of the datasheet clearly explain the color depth that can be achieved at source level for a static image (e.g. a 16-bit png) to go to that nice sink ? Is there a better document ?

Thanks !

[DArce]

As I has been mentioned by Kevin, our graphics controllers support Color depth on 32bpp only with no options to override or change this to other color depths.

[CQuar]

Hello, Diego -

Thanks so much for chiming in.

If 32bpp is the upper limit, is there a way to achieve 30bpp with no transparency ?

Also what gfx stages limit color depth to 32bpp: memory/config interface, display pipes, panel fitting, transcoders A, B or C, eDP mux, Transcoder eDP*/DP encoder . portMUX, etc... ?

At least can you point me to a document that evidences these limits ?

Thanks,

Christopher

[DArce]

Let me further check for this and give you a response for that.

[CQuar]

Thanks Diego -

Maybe you could check for the Xeon E3-12nn v3 as well.

This is for static 2D images such as 16bpc *.png or *.tif or *.jxr photos that I'd like to see at 10bpc or above.

Regards,

Christopher

[DArce]

Alright, i'll add it to my notes on this.

I'll let you know as soon as possible.

[DArce]

For further support and information for this matter you need to refer to the Intel® Premier Support Web site. If you have access to Intel Premier Support, please submit your questions there. If you are unsure if you have access to Intel Premier Support, please contact your Intel sales representative for assistance. Otherwise, request support from your motherboard manufacturer, computer manufacturer, or Intel® Authorized Distributor.

A list of our distributors can be found at the following web site:

http://cache-www.intel.com/cd/00/00/08/99/89937_89937.pdf http://cache-www.intel.com/cd/00/00/08/99/89937_89937.pdf

[CQuar]

Hello, Diego -

First I want to thank you wholeheartedly for your insight.

Second and assuming I find the answer as to whether the 4th generation Core graphics can handle 10bpc or even 12bpc from memory/interface to sink, is it highly confidential ? In other words can I post the answer here or is everyone expected to contact either Intel Premier Support, motherboard manufacturer, computer manufacturer or Intel Authorized Distributor ?

Regards,

Chris

[DArce]

Deep Color is part of the HDMI 1.4 specifications. With Intel graphics (4th generation Core graphics), HDMI Deep color is not supported with 4K resolutions, for example 4096 x 2304 or 3840 x 2160.

What is the video resolution that you are trying to use?

[CQuar]

Deep Color was introduced in 2006 with HDMI 1.3, yet the term means 10bpc or above and not exclusive to HDMI.

HDMI 1.4 increased bandwidth from 225MHz to 340MHz (allowing an 8.16Gbps payload), so as to cover 4K, yet reducing frame rate to allow deeper color, so for instance a 2160p24 30bpp would require a 5.97Gbps payload that's well below what HDMI 1.4 offers (as it could even handle a 2k4k @30Hz with 30bpp)

This is just to address your statement : "Deep Color is not supported with 4K resolutions"

Furthermore, I was questioning any applicable connectivity offered by the processor, not only HDMI, but also DisplayPort (17.28Gbps payload for version 1.2) or Thunderbolt 2 implementation.

In my case, I only need 3840x2160 @24Hz with 10bpc.

Also not to worry about how I'll connect to my display; I'll buy anything it takes, no matter how expensive, to benefit from the 7.5 gfx performance.

[DArce]

I have to check what will be the maximum resolution supported for Deep color, however I do confirm that this is not currently supported on 4K resolutions with Intel(R) graphics.

[CQuar]

Hello, Diego -

Where did you read that deep color was not supported on 4k resolutions, or who stated this ?

Also I am only doing 2160p, that's a bit less than 4k, so I am more interested in 3840x2160 progressive, 24Hz at 30bpp (10 bits per color).

Thanks,

Christopher

[DArce]

Let me clarify that this is only on Intel Graphics controllers, not in the HDMI specification itself.

Are you seeing any information on our web site where something else is being stated? We may need to correct this in that case. Or are you seeing this information from a third party? What is the URL where this information can be found.

[CQuar]

Hello, Diego_Intel -

After reaching out to motherboard manufacturers (as suggested in June by Intel, on the basis that motherboard implementation might result in different levels of performance), they are starting to get back to me with Intel information given to their engineers in Taiwan, and I found that some 4th Gen Core boards are capable of 36bpp at 1080p, and that the latest CustomModeApp.exe (3257) is still not offering 36bpp for that resolution.

From a licensing standpoint, even if HDMI pressured Intel not to offer 10bpc as per paragraph 2 of section 6.2.4 of HDMI 1.3 of June 22, 2006, forbidding any negotiation between sink & source if below 12bpc (even though the human eye can't discern more than 10bpc), the performance requirement is met for HDMI, thus the configuration utility packaged with the driver is at stake. DisplayPort never set limits and until HDMI 2.0 is out, is certainly capable of payloads well above gfx 7.5, so at least this confirms that the configuration utility is, to say the least, questionable.

The part that's puzzling to me now is how you determined initially that the graphics controller was limited to 32bpp, as well as Intel_Diego.

Thanks,

Christopher

[Allan_J_Intel1]

I am sorry for the misunderstanding but correct values are only 24, 30 and 36 bpp, 32 is referring to the color depth.

Allan.