BD85, YCbCr, 4:4:4 and Deep Color

[hydrogin]

Hi Chris - enjoyed your review of the BD85. It was one of the most informative reviews out there and helped me make a decision to purchase one.

I just read your post on deep color:

http://forum.bigpicturebigsound.com/...eep-color.html

Do you know if the BD85 is one of those players you mentioned that perform interpolation to create useful data beyond 8-bits per color channel? Otherwise, I would assume when deep color is enabled on my BD85 and Panasonic G20 plasma, the additional bits sent over HDMI are just padded with zeros?

What other brand BDP's do this color interpolation, Oppo?

Also, as you noted, the BD85 optionally up-samples the YCbCr(4:2:0) on discs and outputs YCbCr(4:4:4). I believe that's actually the default setting and allows us to get more color information for more pixels (less color compression). Do you know whether the Panasonic G20/G25 or VT20/VT25 plasmas can actually make use of the YCbCr(4:4:4)? If not, does the plasma just throw away some of the info when converting internally to RGB? And in this case, any advantages to changing the BD85's output to YCbCr(4:2:2) which I assume the plasma must support directly?

Finally, just wondering if there are any consumer-level deep color sources out there now? The last I heard, some camccorders were coming out with more than 8-bits per color channel. Not that I want to buy a camcorder

[MrBoylan]

Hi Chris - enjoyed your review of the BD85. It was one of the most informative reviews out there and helped me make a decision to purchase one.

I just read your post on deep color:

http://forum.bigpicturebigsound.com/...eep-color.html

Do you know if the BD85 is one of those players you mentioned that perform interpolation to create useful data beyond 8-bits per color channel? Otherwise, I would assume when deep color is enabled on my BD85 and Panasonic G20 plasma, the additional bits sent over HDMI are just padded with zeros?

Yes, the BD85 can output at least 10 bits per color channel (30-bit Deep Color output) through its digital filtering process in the Uniphier's chroma upsampling stage. It may even support 12-bit color but I'm not 100% sure about that.

What other brand BDP's do this color interpolation, Oppo?

Some Pioneer players. The OPPO and some Denon players may do it as well. This isn't something we usually cover in that much detail in our reviews so I wouldn't claim to be the definitive source on which players include this feature.

Also, as you noted, the BD85 optionally up-samples the YCbCr(4:2:0) on discs and outputs YCbCr(4:4:4). I believe that's actually the default setting and allows us to get more color information for more pixels (less color compression). Do you know whether the Panasonic G20/G25 or VT20/VT25 plasmas can actually make use of the YCbCr(4:4:4)? If not, does the plasma just throw away some of the info when converting internally to RGB? And in this case, any advantages to changing the BD85's output to YCbCr(4:2:2) which I assume the plasma must support directly?

Both the G25 and the VT20/VT25 support 4:4:4 color inputs natively so you can get the benefit of this processing on those TVs. And yes, the 4:4:4 output is on by default and the BD85 includes improvements in this chroma processor over its predecessors (BD60/BD80) and even over the BD65 which uses the older chroma upconversion processor.

Finally, just wondering if there are any consumer-level deep color sources out there now? The last I heard, some camccorders were coming out with more than 8-bits per color channel. Not that I want to buy a camcorder

There are camcorders that support xvYCC color, but this is not the same thing as Deep Color. xvYCC color takes advantage of the full 8-bit range (1-255) for color mapping, which extends the color gamut over the standard Blu-ray and DVD color encoding. I do not know of any "native" Deep Color source components at this time so really only the color processing circuitry of certain high end Blu-ray players (including the BD85) can take advantage of it, and even then only by interpolating (or extrapolating) the additional color precision lost in the 8-bit encoding process.

Hope that helps. I moved this into its own thread as I think it might be a tpoic of some interest to others.

Regards,

-Chris

[hydrogin]

That is great information Chris. The BD85 seems even more of a bargain now that I understand its capabilities a little better. I'll make sure to leave YbCbCr(4:4:4) and deep color enabled in my video chain.

Based on your BD85 review, it sounds like BDP's with YCbCr(4:2:2) output are somewhat common. I'm wondering if support for YCbCr(4:4:4) inputs is common among HDTV's these days? In other words, can many/all sets out there take advantage of the additional color information the BD85 optionally outputs?

[EDIT: I just re-read your post on deep color (link in my original post) and found out not all displays will support YCbCr(4:4:4).]


Related to the above question, it seems that before a TV internally generates the R, G, and B values for all its sub-pixels, it needs to have Y, Cb, and Cr info for each pixel. If there is only YCbCr(4:2:2) arriving at the TV (i.e. half the pixels don't have chroma info) does the TV do its own chroma processing to fill in the gaps?

I suppose that processing could be as simple as just grabbing a chroma value from a neighboring pixel. Or it could be something fancier, maybe similar to what the BD85 does to get from 4:2:0 to 4:4:4. The last scenario I could imagine is, maybe its taken care of by the BDP ... after the BDP up-samples to 4:2:2, a pixel that only has luma info gets stuffed with a neighboring pixel's chroma info before being sent out. If this were what all BDP's with "real" 4:2:2 outputs did, then the TV would always receive 4:4:4 (regardless of quality) and not have to differentiate between 4:2:2 and 4:4:4 inputs. But that seems like a cheesy way to do it

[elwaylite]

Thanks for the review! I'm a newbie here but had to join to pick your brain.

Chris,

Would you know if the S2 (I just bought a TC-P58S2) can take advantage of the YCbCr 4:4:4? Reading Panny's site, I cannot find anything that separates the 3 models with regards to this feature. All just say 'Deep Color" "Yes".

Also, Im connecting a DVDO Duo tomorrow, and have emailed them on it's abilities with YCbCr 4:4:4.

TIA!

[MrBoylan]

Thanks for the review! I'm a newbie here but had to join to pick your brain.

Chris,

Would you know if the S2 (I just bought a TC-P58S2) can take advantage of the YCbCr 4:4:4? Reading Panny's site, I cannot find anything that separates the 3 models with regards to this feature. All just say 'Deep Color" "Yes".

Also, Im connecting a DVDO Duo tomorrow, and have emailed them on it's abilities with YCbCr 4:4:4.

TIA!

Welcome to the forum, and sorry for the delay. I'm on the road right now in Baltimore for a press event at Polk's HQ. As far as I know, for this year's Panny TV lineup, only the G20, G25, VT20 and VT25 support the direct 4:4:4 input from the BD65 and BD85. But if you already have the player (or can borrow one), then you can verify yourself. The BD85's Playback Information Window will show you if the 4:4:4 output is active when watching a Blu-ray Disc on the set. If the set does not support 4:4:4 then it will display as 4:2:2. The Playback Information Window is activated via the "Functions... Disc" menu (I think).

The BD65 does not have this, but the BD80 and BD85 do.

This doesn't mean the S2 isn't a good set. It just means it might not be able to take advantage of the full processing power of the BD85.

Regards,

-Chris

[elwaylite]

Thanks. It is sending 4:4:4, and we have also verified with a DVDO Duo. The S2 can accept 4:4:4. I used my BD85 and the S2 last night, to check the Chroma tests on the Spears and Munsil disc, and it seems to do well by their patterns.

[hydrogin]

The BD85's Playback Information Window will show you if the 4:4:4 output is active when watching a Blu-ray Disc on the set. If the set does not support 4:4:4 then it will display as 4:2:2.

Interesting, that implies the YCbCr level is negotiated between the blu-ray player and the display via HDMI. I don't own a video scaler/processor but I wonder if that will also indicate YCbCr level?

[elwaylite]

I just installed my DVDO tonight. Directv is YCbCr 4:4:4 24 bit in to the Duo. The BD85 is 4:4:4 YCbCr 36bit out, and thats what goes to the TV.

[MrBoylan]

Interesting, that implies the YCbCr level is negotiated between the blu-ray player and the display via HDMI. I don't own a video scaler/processor but I wonder if that will also indicate YCbCr level?

Yes, 4:4:4 capability, as well as Deep Color support is identified by the display device in the HDMI/EDID handshake.

-CB

[MrBoylan]

I just installed my DVDO tonight. Directv is YCbCr 4:4:4 24 bit in to the Duo. The BD85 is 4:4:4 YCbCr 36bit out, and thats what goes to the TV.

A little surprised that the DIRECTV box is able to output a 4:4:4 signal, but the fact that it's only 8-bit per color (24-bit total) implies that its processing is probably not too advanced.

If the BD85 is outputting 4:4:4 36-bit that means it is "upsampling" the chroma signal from 8 bits to 12-bits per channel during the chroma upconversion stage.

I'm not that familiar with the DVDO box, does it have some kind of on-screen display that reports on the TV's capabilities in the areas of color processing and resolution/frame rate?

-CB