How important is 10-bit color, really?

[Penton-Man]

Originally Posted by Robert Zohn

I prefer DCI for several reasons.
- First, it currently available with thousands of Hollywood movies that are already graded for DCI so no need to create new and difficult to produce content.

Agreed, P3 is easier (cheaper, etc.) and the studios have desired it for UHD as expressed in past postings in the ‘4K Movie Releases’ thread or other threads in the Blu-ray Tech forum for months, perhaps over a year now.

Knowledge is best when *uncompartmentalized*.

[Penton-Man]

Originally Posted by Robert Zohn

I prefer DCI for several reasons.
- Second, for filmmakers to invest in new rec. 2020 equipment is too much of a burden as they are already considering buying HDR cameras and supporting equipment.

High end digital cameras (and film cameras, for that matter) have been ‘HDR capable’ for years.

But yes, in the case of BT.2020 colorimetry, it would require changing the entire content preparation workflow. It must be supported from acquisition (Sony’s F65 S-Gamut is probably the closest match) through editing and color grading facilities, including support in studio monitors. See past discussions with Richard Paul, also from months ago.

[Penton-Man]

Originally Posted by Robert Zohn

- Fifth, displays cable of delivering 12bit and what is really needed to display HDR and rec. 2020 color is more likely 16bit would be very expensive to develop and build.

bolding by me.

Wrong, with PQ coding, 12 bits would be plenty sufficient even for ACES color primaries even at 10,000 nits.

[Penton-Man]

Originally Posted by Robert Zohn

I much prefer HDR and P3. Better color, higher contrast ratio and something Hollywood, the BDA, TVs and projectors can manage...

Not a particularly bad choice/compromise....once the ambient lighting issue has been solved.....which IS a significant issue.

[Robert Zohn]

Originally Posted by Penton-Man

High end digital cameras (and film cameras, for that matter) have been ‘HDR capable’ for years.

But yes, in the case of BT.2020 colorimetry, it would require changing the entire content preparation workflow. It must be supported from acquisition (Sony’s F65 S-Gamut is probably the closest match) through editing and color grading facilities, including support in studio monitors. See past discussions with Richard Paul, also from months ago.

Thanks for the replies to all of my many points. I knew you would get to like me.

So as you can tell I love and appreciate your technically correct remarks. However, my reply on this item is that having the content on film or digitally is only the first step in a very large multi-faceted process to get HDR to our home displays.

And not sure why you would say 10,000 nits, we're looking to go from the now standard 100 nits to x10, 1,000 nits to achieve what is commonly used when we refer to HDR.

Plus I stick to my estimate that we actually need more than 10bits or even 12bits. I can't go along with a lot of digital compression.

Finally, we'll need these new CES 2015 expensive 10bit OLED and QDOT displays and if I get my way at least 12bit panels. So now we're talking about the actual physical full 12bit OLED 4K panels. If we go to 12bit the costs are even higher.

God bless, LG, Sony, Samsung, Sharp and all of the other manufacturers for bringing us your beautiful TVs!

-Robert

[Mr Kite]

I started another thread with this link but i think it is relevent here also:

http://www.hollywoodreporter.com/beh...holders-761160

[Penton-Man]

Originally Posted by Robert Zohn

Thanks for the replies to all of my many points. I knew you would get to like me.

I offered my hand….https://forum.blu-ray.com/showthread...t#post10224852 despite not receiving any social reciprocity in “Display Theory and Discussion” nor in my regular neck of the woods. If not an oversight, some might consider that rude.

For past prospective , Dave Vaughn and I still pleasantly communicate regarding such things as references for her daughter to film school or Hollywood internships.

[Penton-Man]

Originally Posted by Robert Zohn

And not sure why you would say 10,000 nits, we're looking to go from the now standard 100 nits to x10, 1,000 nits to achieve what is commonly used when we refer to HDR.

Simple, because evidence based research (by those for instance on working groups in SMPTE) have shown that 12bit is sufficient for even up to 10,000 nits. Certainly there is enough bitrate headroom for lower luminance outputs such as 1000, 800, 400 nits, whichever the individual vendors may offer. And on a similar note, when I said “ACES primaries”, like so, certainly P3 or BT. 2020 primaries would be no problem.

[Robert Zohn]

Originally Posted by Penton-Man

I offered my hand….https://forum.blu-ray.com/showthread...t#post10224852 despite not receiving any social reciprocity in “Display Theory and Discussion” nor in my regular neck of the woods. If not an oversight, some might consider that rude.

For past prospective , Dave Vaughn and I still pleasantly communicate regarding such things as references for her daughter to film school or Hollywood internships.

David Vaughn is a value friend and I am a very big supporter for Haiti. In fact, our local Scarsdale Rotary where I am an executive director we granted $34k to build a military water filtration plant that brought clean water to a village of 1,600 Haitians.

Thanks for all you do! I am sincerely appreciative!

-Robert

[Richard Paul]

Originally Posted by RWetmore

Yeah, though I tend to think 10 bits is not quite sufficient for rec. 2020 and 12 bits is really needed; however, I sense the BD association is not going to give us more than 10 bit for UHD Blu-ray. We'll see though I guess.

The Rec. 2020 color space is about twice the size of the Rec. 709 color space. When going from 8-bit video to 10-bit video you get 4 times the precision for each color component and 64 times the number of color combinations. 12-bit video is mostly for HDR which can have a maximum brightness 100 times higher than what is currently used for TV.

Originally Posted by Robert Zohn

I prefer DCI for several reasons.

- First, it currently available with thousands of Hollywood movies that are already graded for DCI so no need to create new and difficult to produce content.

- Second, for filmmakers to invest in new rec. 2020 equipment is too much of a burden as they are already considering buying HDR cameras and supporting equipment.

Rec. 2020 is going to be used by UHDTV and while improving color does increase the cost that is also true for 4K resolution and HDR. As for DCI P3 it was used since that was what could be done ten years ago with Xenon lamps. Technology has improved greatly since than and several consumer display technologies can now go far beyond the limits of Xenon lamps.

Originally Posted by Robert Zohn

- Third, we already know and love what DCI color looks like as it's been in the movie theaters for many years.

DCI P3 was released in 2005 and it has a smaller color space than film which can be seen in this diagram showing different color spaces. To fully capture the color of film the Rec. 2020 color space would be a good choice.

Originally Posted by Robert Zohn

Plus I stick to my estimate that we actually need more than 10bits or even 12bits.

Here is a link to an article that shows how 12-bit video can encode a brightness of 10,000 nits.

[RWetmore]

Originally Posted by Robert Zohn

I prefer DCI for several reasons.

- First, it currently available with thousands of Hollywood movies that are already graded for DCI so no need to create new and difficult to produce content.

- Second, for filmmakers to invest in new rec. 2020 equipment is too much of a burden as they are already considering buying HDR cameras and supporting equipment.

- Third, we already know and love what DCI color looks like as it's been in the movie theaters for many years.

- Forth, the bandwidth to deliver HDR and rec. 2020 is not reasonably possible. It's also very difficult to get displays to accurately render rec. 2020 color.

- Fifth, displays cable of delivering 12bit and what is really needed to display HDR and rec. 2020 color is more likely 16bit would be very expensive to develop and build.

I much prefer HDR and P3. Better color, higher contrast ratio and something Hollywood, the BDA, TVs and projectors can manage and much more likely to be streamed to your home.

-Robert

Interesting points. Does the BDA actually think 10bit color (presumably at 4:2:0) is sufficient for rec. 2020? Any info regarding that?

[RWetmore]

Originally Posted by Richard Paul

The Rec. 2020 color space is about twice the size of the Rec. 709 color space. When going from 8-bit video to 10-bit video you get 4 times the precision for each color component and 64 times the number of color combinations.

That's an interesting and good way of looking at it, but with 8bit rec. 709 we still get banding. Will there be banding with 10bit rec. 2020 seems to be the fundamental issue and question. That is, is twice the precision provided by 10bits enough to eliminate banding for rec. 2020? I would think 12bits is for sure, but for 10bits I'm somewhat skeptical.

[Tech-UK]

Originally Posted by RWetmore

That's an interesting and good way of looking at it, but with 8bit rec. 709 we still get banding. Will there be banding with 10bit rec. 2020 seems to be the fundamental issue and question. That is, is twice the precision provided by 10bits enough to eliminate banding for rec. 2020? I would think 12bits is for sure, but for 10bits I'm somewhat skeptical.

10-bit should be sufficient for content shot on film (its rare to see banding in films shot on film, unless its CGI or something has been altered in the digital domain). 10-bit dithered should be sufficient for digitally shot films and animated features, I would of thought.

May not even need to dither if the source is good.

The problem is, will the studio's want to provide an image to the consumer market that matches or betters what can be seen in the cinema?

[Richard Paul]

Originally Posted by RWetmore

That's an interesting and good way of looking at it, but with 8bit rec. 709 we still get banding. Will there be banding with 10bit rec. 2020 seems to be the fundamental issue and question. That is, is twice the precision provided by 10bits enough to eliminate banding for rec. 2020? I would think 12bits is for sure, but for 10bits I'm somewhat skeptical.

There would be less banding with 10-bit Rec. 2020 than there would be with 8-bit Rec. 709 but I do expect 12-bit video to be used for professional applications. I would be happy if 12-bit video was added to Ultra HD Blu-ray but there are several reasons why that is unlikely to happen.

[Penton-Man]

Originally Posted by Robert Zohn

David Vaughn is a value friend and I am a very big supporter for Haiti. In fact, our local Scarsdale Rotary where I am an executive director we granted $34k to build a military water filtration plant that brought clean water to a village of 1,600 Haitians.

Thanks for all you do! I am sincerely appreciative!

-Robert

Thank you and I am impressed with your outside (A/V retail sales) endeavors. On that note, although, people never hear about it, there are several ‘Hollywood’ people that do their humble part for society by…http://www.redcross.org/blood to make a difference in others’ lives.

[Penton-Man]

Originally Posted by RWetmore

That's an interesting and good way of looking at it, but with 8bit rec. 709 we still get banding. Will there be banding with 10bit rec. 2020 seems to be the fundamental issue and question. That is, is twice the precision provided by 10bits enough to eliminate banding for rec. 2020? I would think 12bits is for sure, but for 10bits I'm somewhat skeptical.

In general, any wider color gamut expands the distance between consecutive codes given the same bit depth. The following figure shows the histogram of color differences ∆ Eab* between all consecutive 8-bit codes for BT.709 primaries and the primaries of BT.2020…



The mean and max values are listed in the next table as pictured below. The mean of ∆ Eab* for UHDTV is 35% larger than that of HDTV. This means that 1 more bit of precision is sufficient to make the ∆ Eab* equal to or less than that of HDTV. The maximum value for UHDTV would be below 1 if 10-bit is employed.



When do people think consumer TV manufacturers will actually offer to the public widespread 10 bit panels capable of 12 bit processing, i.e. something like this - http://www.flandersscientific.com/index/cm250.php but with a 4K rez LCD technology?

[HeavyHitter]

Originally Posted by Tech-UK

The problem is, will the studio's want to provide an image to the consumer
market that matches or betters what can be seen in the cinema?

I don't think the studios care about this very much. People go to movies primarily for the outing, overall experience and massive screen - something no home will ever be able to provide so there is not much fear. It's not about picture quality per se.

My pro calibrated JVC front projector produces far more contrast and better blacks than any commercial theater I've been to and gives a better overall image with Blu-ray even with it being 8 bit, rec 709. I know a number of people on this forum with quality set-ups can say the same. I just watched Gaurdians of the Galaxy the other night and thought to myself, objectively, just how much better it looked compared to the AMC theater viewing I saw it last year.

[Tech-UK]

Originally Posted by HeavyHitter

I don't think the studios care about this very much. People go to movies primarily for the outing, overall experience and massive screen - something no home will ever be able to provide so there is not much fear. It's not about picture quality per se.

My pro calibrated JVC front projector produces far more contrast and better blacks than any commercial theater I've been to and gives a better overall image with Blu-ray even with it being 8 bit, rec 709. I know a number of people on this forum with quality set-ups can say the same. I just watched Gaurdians of the Galaxy the other night and thought to myself, objectively, just how much better it looked compared to the AMC theater viewing I saw it last year.

I feel the same when I watch a film on my calibrated Kuro, but the specifications are currently better on the cinema side.

Its whether or not the consumer market sees 12-bit, 4:2:2.

[Penton-Man]

Originally Posted by HeavyHitter

My pro calibrated JVC front projector produces far more contrast and better blacks than any commercial theater I've been to...

D-Cinema projectors generally are in the 2000-2500:1 contrast range. Next gen projectors will be better.

[Penton-Man]

Originally Posted by Tech-UK

Its whether or not the consumer market sees 12-bit, 4:2:2.

As to 4:2:2, well, without totally spilling the beans, an insight was offered up to people on Jan. 9 who could work it out… https://forum.blu-ray.com/showthread...g#post10258114