icc / lut plugin for vegas(color management)

arbory wrote on 12/14/2009, 8:48 AM
hi

I want to share an idea with i had about a ICC / LUT fx plugin for vegas, which should be quite easy to implement. I don´t know if it´s really easy possible, but it would be great to have a basic color management implementet possibility in vegas, which may become useful when more and more wide gamut displays get common in the near future.

the video fx plugin should do the following:

if you choose to use the plugin at video fx output it would be possible to color management the monitor with the video preview.
choose the ICC profile of the monitor an then you have a calibrated output like in photoshop
(video color space -> (ICC of monitor - LUT) -> monitor color space

an reversed option would also be nice, when applying the ICC / LUT plugin to an event or track:
(image/ video- file colorspace -> (ICC / LUT of file) -> video color space)

the last option should be an 16-235 option (like studio rgb <-> computer rgb)

i was thinking about this when, i was using the secondary display preview settings, there you can also choose a profile and the 16-235 option.
but i think this option is not really a color management option - i tried some very different icc profiles, but the only thing which changes seem to be the gamma and not the color?

the possibility with an ICC / LUT video fx would be endless, also for creative abuse:

1. you can make a sort of basic color management for your monitor where your preview window is on.
2. apply a color profile on an image, which has another color space (eg. adobe rgb of an photo, without changing it in photoshop first to srgb)
3. apply a LUT like in cineforms first light, for a specific look
4. endless combinations of 1,2 and 3

of course it would be nice if vegas would have a full color management in future versions a la photoshop, but the video plugin fx version would be much easier to implement and very, very flexible. not only for color management - also for color correction and color grading.

If i could only have more programming skills.....

i don´t know if it´s really so simple - tell me if it´s not....

or is somewhere out there a ICC / LUT virtualdub filter which could do the same
(when using it with plugin adapter) ?











Comments

GlennChan wrote on 12/15/2009, 9:24 PM
1- Wide gamut would need to be supported throughout the chain...

so you need Vegas to support it (e.g. turn off the clippers)
not easy because a lot of plugins will make simplifying assumptions about clipping illegal colors (and by extension, wide gamut colors)

and then you need consumers players + TVs to support wide gamut. It's going to be a huge mess initially. And people will need some way of making wide gamut look ok on normal TVs. And oh yeah... a lot of footage has long periods where there are no noticeable wide gamut colors.... so the viewer might be wondering where the benefit is.

2- Now if you are making normal video, you only have to target a SINGLE medium / display device. So you can just buy a broadcast monitor and that is your target reference. In theory all broadcast monitors should look the same. (For CRTs and professional broadcast monitors, they all look pretty close. But now there are various display technologies and they look different.)

You wouldn't need any LUTs or sophisticated color management.

3- Otherwise, if you needed LUTs, a simple solution would be to implement it in the monitor... which some manufacturers do (e.g. eCinema, Cinetal) and there are other ways of doing it.
arbory wrote on 12/17/2009, 7:38 AM
1-
no it´s not about working in a wide gamut color space - i just want to stay in video color space (rec709, pal , etc..) which is quite close to srgb as far as i know.
i want to get video colors (quite) right on video preview window.
the point is, if i buy a new pro lcd in the future, 90% of them are wide gamut displays.
the video preview on a wide gamut display can be far of srgb (extreme saturated candy reds and greens...) when you use an software which is not supporting color management (like vegas)

2 - i know, if you have an external broadcast monitor everything would look fine, or also if you have an display with hardware calibration like eizos cg, where you can choose an target color space.
the colors are also quite ok if you use an monitor near srgb color space. you just add an fx (color correctior or levels) with the "Studio RGB to Computer RGB"-preset for video levels.
and here in this chain an ICC / LUT fx plugin could be very useful:
To color correct the RGB colors from Vegas through a color profile for the preview window. a cheap color management.

3 - this fx plugin could be used very flexible, not only for color managed previewing of the video output on your monitor. With an (3d) LUT you can do all sort of color correction/manipulation, to achieve a certain look (from bw, sepia, cross processing to quite crazy color manipulation).


GlennChan wrote on 12/17/2009, 7:29 PM


With an (3d) LUT you can do all sort of color correction/manipulation, to achieve a certain look (from bw, sepia, cross processing to quite crazy color manipulation).
You can do that with a 3-D LUT, but there are some situations where you get banding.

If you think about the color curve... with a 3-D LUT that's 65x65x65, you're limited to making the curve out of 64 straight lines (and the points have to touch 0, 3, 7, ... 255). If the original curve is extremely bent/curved in one area, you get angles in the resulting curve and that doesn't work visually when dealing with gradients.

But what you really want is to just convert the primaries correctly... you can do that, and you don't need to approximate the calculations with a 3-D LUT.

a cheap color management.
What it really entails is taking a turd and polishing it. You could take a consumer monitor and try to get the most out of it. eCInema used to do that with the Apple Cinema display (consumer LCD) + their hardware processing box. But there are certain limitations with that approach... that's why I call it trying to polish a turd.

If you had a consumer TV or LCD monitor (preferably a TV), there is some signal processing you can do to make the colors better. You could try to make the primaries of the TV match the standards better... but to do that, you'd need some way of measuring the TV................

If you want to do this, your budget would probably be in the ultra-low budget category anyways. And it would cost something to measure the particular model monitor that you have... that doesn't make sense to me.
For $600, you can get a SD CRT broadcast monitor. (Or at least, you used to be able to do that.) And the quality of that monitor is pretty damn good and it's good enough to pass broadcasters' QC with it.

With cheaper solutions, trying to polish a turd doesn't make much sense because consumer equipment has all these other flaws that you can't get rid of. Anything but a CRT TV/monitor can't handle interlacing well. (Signal processing to de-interlace video doesn't really work.)
And of the consumer CRTs, they may have weird colors... you could try to process that by digitally altering the signal (which loses a bit in the process because some of your bits are wasted, and I believe you have to deal with dithering)... but to do that you need to measure the monitor and pay for some sort of measurement device (oh yeah, the cheap ones are no good)... you might as well get a broadcast CRT.
arbory wrote on 1/5/2010, 12:20 PM
i understand your point, but i have no intension "polising a turd"
i think we are talking about different things!
i agree, that it is a very good solution to have a (sd) broadcast monitor as a preview, a HQ solution and a quite affordable also.
In the last decade i worked always on sony trinitrons (as main monitors and also with external Broadcast Sony PVMs over firewire/DV). But most of the time i had no need for an external preview - i just worked on trinitrons and used one of the "Studio RGB to Computer RGB" fx possibilities in vegas to see the video levels right, and the preview was accurate enough most of the time. The Computer trinitrons which all are quite near the srbg color space were calibrated with a spyder, which helps a lot when they get older and over the years. The differences in color managed applications like photoshop to the unmanaged windows desktop and other programs where minor.
Working on laptops, and even on good LCDs was unthinkable without an external preview crt monitor or TV some years ago.
But time is changing, and the LCD technology has been getting better and better over the years. Still a lot of crappy displays out there, but also very good ones with a good color gamut and viewing angles.
I started this thread, because i was thinking about all the new wide gamut displays, which will even find their way to laptops next years.
wide gamut sounds nice first - but they are unusable without color management!
Just today i recieved an Eizo FX2431. A great allround monitor with all the different inputs (from composite,s-video, component, hdmi,..), with all the different (real not simulated like in other lcds which always stick to 60HZ) refreshrates 24,25,30,48,50,60Hz. Great screen, very good black level and a quite good viewing angle (but nothing compared a CRT).
So - after a calibration with my spyder3 i compared the color managed output (srgb) with the unmanaged, and there is quite a huge difference.
to get an idea about it - i have posted an image for another (non-vegas) discussion:

http://www.flickr.com/photos/45383087@N04/4248834284/

so - to get to the point:
the whole thread was not about the advantage of an external broadcast (crt) monitor, and whats the best and "cheapest" solution - it is about editing with preview on normal computer monitors and even laptop displays. Until last years most LCDs had too less color gamut, now they get too wide gamut without a color management. video color spaces are near srgb, and on wide gamut displays vegas is not usable (speaking of color correction) without an second preview monitor.
Now even Firefox has a color management, Quicktime on snow leopard has it, and all serious graphic/video application will have to follow.
So, when color management comes with Vegas?
That´s the point when i was thinking about this icc-fx-plugin:
it would be really "cheap" and dirty, easy to implement, but flexible :
I have a icc-profile from my calibrated display (or any other icc) - load it into the icc-fx-plugin and get a color managed output for my display (or an other color transformation, correction depending on the icc-profile).
(before repeating look at my earlier posts)
color manipulation with an icc-profile could be a quite unique feature in vegas

but while i talking again too much, maybe the guys at sony have another sort of color management for vegas already in the pipline for v10........ ?