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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

16:8:8 Color Sampling?

One more try

One more try

Tell you what, to draw line under this (until Sony or whomever it was that invented the term explains what 16:8:8 or 18:8:8 means)

We'll continue to use 4:2:2 and 4:2:0 and 4:4:4 in their accepted meaning: the ratio of samples used for the signal components Y, Cb, Cr or R, G, B.
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Workflow Wizard
 
Sorry to drudge up an old thread…

I was away and I feel I never quite got to respond. I just wanted to thank all those posters who, like Graeme and M Most, gave some of their time in explanation on this subject. I’ve had this one wrong for many years. It’s never been an issue for me in my business that the more subtle details of the ratios got lost in their broader meaning. But it is nice to finally have it fully and concisely explained. So I thank the posters that chose not to jeer those of us who have been a little hardheaded about what we learned and instead opted simply to try and inform us.

And I think Stuart’s summation is perfect.
 
My take on this is that 8:8:8 was also used for RGB codecs, symbolizing 8-bit per each R, G & B color channel when it came to Vialta (Sony's HD telecine / scanner). So I would only assume that 16:8:8 refers to 16-bit Green with both Red and Blue having 8-bit each. This would be logical with standard bayer pattern CMOS sensor which has double the Green photosites as compared to Red and Blue...

Just my two cents...
 
16:8:8

16:8:8

Peter Majtan said:
My take on this is that 8:8:8 was also used for RGB codecs, symbolizing 8-bit per each R, G & B color channel when it came to Vialta (Sony's HD telecine / scanner). So I would only assume that 16:8:8 refers to 16-bit Green with both Red and Blue having 8-bit each. This would be logical with standard bayer pattern CMOS sensor which has double the Green photosites as compared to Red and Blue...

Just my two cents...
Click to expand...

Peter I think you are confusing bit depth and color component sample ratios - the 8:8:8 nomenclature meant RGB at double the resolution of SD. i.e. standard definition RGB was referred to as 4:4:4, so double resolution RGB was called 8:8:8.
 
Stuart English said:
Peter I think you are confusing bit depth and color component sample ratios - the 8:8:8 nomenclature meant RGB at double the resolution of SD. i.e. standard definition RGB was referred to as 4:4:4, so double resolution RGB was called 8:8:8.
Click to expand...

Stuart, I was just referring to how SONY used the 8:8:8 nomenclature in relation to the Vialta telecine and since it was Sony who posted the 16:8:8 - this is the only explanation I can foresee. In no way I am saying they are OK to use it in tis way, just trying to explain their thinking...
 
Sony Telecine

Sony Telecine

Perhaps. But what Sony said back then was -

"The SDTV channels can be switched between 525 and 625 TV line standards. By adding a second SDTV channel, simultaneous transfer to 525 and 625 standards is achieved. Picture resolution can be selected as 4:2:2, 4:4:4, 8:4:4, or 8:8:8 via single, double, or triple SDI (Serial Digital Interface) connections"

It's pretty clear from that 8:8:8 as used then was a description of resolution and not bit depth.


Still mystified by 18.8:8 though :-)
 
It's the 1981 and Toyah comes on Top of the Pops and sings "It's a mystery, it's a mystery"

Graeme
 
Bruce Allen said:
http://provideocoalition.com/index.php/sony/story/wherefore_444/
...explains their viewpoint:

"We proposed that if “4” served SD, then the 1080-line HD world should reflect the far higher sampling frequency of 74.25 MHz. The arithmetic is 74.25/13.5 x 4 = 22. Based on this impeccable logic, we told anyone who would listen that the 1080-line HD counterpart of 4:2:2 should be called “22:11:11.

Nobody listened.

The result is that the nomenclature has lost any tie to sampling frequency and is applied to any image, regardless of resolution. In today’s crazy, mixed-up world, 4:2:2 describes all three of the following images:"

"The ratios ignore differences in image sizes. In the days of standard definition, the “4” specifically referred to the ITU-R BT.601 sampling rate of 13.5 MHz. In 525-line 60-Hz parts of the world, this meant a digital image of 720x480. But today, we’ve got a vast range of image sizes from 1280x720 to 1920x1080, 2K, 4K and beyond. Even as 13.5 MHz passes into memory, the 4:4:4 nomenclature lives on, applied to images of all sizes. This often leads to misunderstandings.

Years ago, Internet chat rooms were abuzz with the relative merits of Sony® HDCAM® 24p recording (sometimes described as 3:1:1) versus Panasonic® Varicam® DVCPRO HD® 24p tape recording (sometimes described as 4:2:2). At the time, some commenters supposed that the “3:1:1” format must have fewer color samples than the “4:2:2” format. Because of different image sizes, it wasn’t and isn’t true."

I merely quote it, I don't necessarily agree with it.

Sony is still bitter that its 1080p HDCAM was dissed for being "worse color" 3:1:1 against Panasonic's "better color" 4:2:2 720p. When the 3:1:1 1080p signal actually contained more Chroma info.

And they're bitter that HD was compared to SD.

This time around they have a "8K" camera which records a 4K signal at 16bits per channel, with Y every pixel and chroma every second pixel.

So presumably they decided it was time for bigger numbers. 16 because... it's 4 times more resolution overall? because it's 16 bit?

No idea.

It's just a ratio, I guess ;)

But they're trying to make things very confusing.

Bruce Allen
www.boacinema.com
Click to expand...


I wish somebody within the RED team will give us their own interpretation of this 16:8:8 color Subsampling and how the Monstro sensor can benefit from it .Thank you Bruce .
 
Alain, our own interpretation is irrelevant as it's some new terminology that Sony have concocted for marketing purposes that is essentially meaningless. What RED will do is continue to explain our technology as best as we can and show with images why our approach works well, measures well and looks superb.

Graeme
 
I am Glad you clear this foggy bottom in my mind.As you might know by now i have been tracking your work way before Red and delighted you find out the best of you is yet to come Sir Graeme .
Sincerely yours .
 
I think so too Alain - we just keep pushing things forwards as best as we can. Thanks,

Graeme
 
Nomenclatures are fine, but maybe they should be accompanied by clear variables. Something as simple and straightforward as "1920x1080 Y, 960x540 U, 960x540 V" seems fairly clear and unambiguous compared to "1920x1080 4:2:0 YUV" or even more ridiculous ones like "22:11:00 YUV".
 
You welcome Graeme and wish to have this same conversation with you in 2020 .
By the way you pulled my legs about my request on HDR built in camera,remember?

Alain
 
Me, pull your leg? Surely not! Are you sure it was me or was it the actor who is paid to play me at tradeshows?

Graeme
 
I knew you was up to the challenge and you managed to go beyond my expectations .RED is where you will rich the promise Land Digitally speaking .
It was very nice speaking with you Sir (i mean it ) Graeme .

Alain
 
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