Youtube - Rec.601/709 - Problems - What can be done

[zerowalker]

So basically trying to make a discussion to collect information regarding this.

The old rule has been that Youtube will Always playback at rec.709, so if you convert to that from RGB when you record games etc, you are good to go.

However, i just noticed after playing around with this, that HTML-5 player actually used Rec.601, which totally breaks everything for me, as i have been doing everything in Rec.709 as this is normal for both Youtube and normal use (Rec.709 = "HD").


So what can be done about this?

As far as i know, HTML isn't a plugin and should be Open, so perhaps it's possible to just tell the player to use Rec.709?

Anyone know anything?

[Atak_Snajpera]

if they use 601 for hd content in html mode then you can only ask them to fix that ;)

[zerowalker]

Tell Youtube?

Pretty sure that's worthless, have asked them for many things, only got 1 answer at one time, and it was something regarding VP9 during it's early development.

But may as well try, any ideas where to write, i guess some Google Group or what it's called?:)

[zerowalker]

Well i made a post, tried to explain a bit, think i made quite a mess though: Flash Player and HTML5 uses different YUV->RGB Color Matrixes. (https://productforums.google.com/forum/#!profile/youtube/APn2wQe1OX5p_xOUdESxbCOCeCYmJtQgvCB7T1OvmV5Nkk5HIzj4gBg_bRlO7jtGFrX6w80hV7rJ/youtube/ynR4wcbNBW8/fhpfXVVIMqQJ)

[TheSkiller]

Impressive they still haven't figured out how to handle color coefficients. :rolleyes:

The current behavior, always assuming Rec.709 for YV12 -> RGB conversion during playback, isn't really smart as well, but at least it's something one can work around (because of this all my older 480p and 360p videos play with colors slightly off because they stick to the common sense of using 601 while YT doesn't care). Suddenly doing it the other way around is just dumb.

I hope they finally do their homework and learn about color coefficients.

[zerowalker]

Indeed, and i stated that manually being able to set it would be for the best, and an automatic settings which would go by the Resolution which normally is done by decoders.

But generally, 480p and below (or rather, if original clips are that) should in normal sense be Rec.709.

I would say, rather force Rec.709 than Rec.601, but as said, ideal would be the option to change it.
I don't believe it can be that hard, just set it to some advance setting so people can change if they know about it, and let "normal" people see what they see as they aren't bothered by it.

[kolak]

It's not that obvious, as 601 is mainly assigned for strict PAL/NTSC signals.
There are few companies which use for HD and all non standard (PAL/NTSC) sources Rec.709.
Non one ever specified what color matrix should be used for web content.
It's better to put effort to make sure all files are flagged with color space and decoders respect this flag. Doing it this way you don't have to care that much which one has been used. Choosing color metrix based on resolution is not the ideal solution.

[zerowalker]

True, but overall in the end most HD Content will probably be Rec.709 and SD Rec.601, the goal is to correct majority.
Locking doesn't solve much, so Auto and Manual would be for the best.

This is a thing i can't understand though, how come there aren't Flags telling the Matrix, how come you have to guess all the time?
I know some codecs do, but overall it's pretty much left alone, there is no fluid system for it.

[kolak]

Most formats support storing these flags, problem is that many software does not set/read them.
It's up to developers to implement it properly. Ffmpeg still does not do it in many cases, where ffmbc has this feature implemented. It's all down to respecting specifications or just common sense where spec does not exist.

[zerowalker]

Most formats support storing these flags, problem is that many software does not set/read them.
It's up to developers to implement it properly.

Precisely, that's the thing i meant with "Fluid System".

It's only halfway done, it's like the thing about NTSC being 29.97 instead of 30 just cause of how it needed to be that before.
It's gone so long that the only way to fix it, is to do an overhaul of things, and that won't happen in a long time, especially not in the Internet "Youtube" front.

Which leads down to guessing and manageability of choice, not ideal in anyway, but better that then forcing something, especially Rec.601 when this time around Rec.709 is probably going to be more and more common.