[Andrew Somers]

Based on what you described, I’m going to guess that your mp4 is at a resolution like 720×480 or smaller? (i.e. standard def size) ?? just a guess, but AME may be using the Rec601 colorspace, which uses very slightly different color primaries than Rec709 (which is what sRGB uses). I’m thinking this because Adobe seems to like to assign colorspaces based on
codec and/or resolution — and you’ll notice that AME give you very few options regarding colorspace, OTHER THAN “NTSC or PAL”. I find it interesting that “HDTV” is no where to be found inside AME.

Just as a point of reference, I NEVER EVER use AME straight out of After Effects. If I am going to use AME to create MP4s, I typically go out to ProRes, and then send that ProRes file into AME.

All that said, Adobe licenses “the guts” of what does all the work inside AME from MainConcept. You can read a sample of what the inner workings are capable of in this sample file here: https://www.mainconcept.com/us/getting-started/samples.html?item=1

As you can see, MainConcept can handle a lot of color spaces, but the HOST app needs to use the API to actually make things “go”.

Does Adobe/After Effects send the correct source color information to AME when encoding though AME? I doubt it because Adobe does not even do that correctly in the AE output module !!!!!!!! (By “correctly” I mean not only transforming the color into the correct destination space but also setting the Atom/Headers in the output file to correctly reflect this with the proper FourCC code or profile information — color managed my axx LOL). I suppose Apple is partly to blame here for creating a media container (QT) that does not enforce listing colorspace information in metadata.

ALL THAT SAID: If you are going to be going out to “small” videos (SD NTSC) then you might want to use a Rec601 profile for the chromacities of your working space. It is my opinion that the best results are had when your working space chromacities are identical to your destination chromacities.

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

You can set undo at 99 but it doesn’t mean you get 99.

Undo is limited by available RAM, prOkechukwu size, etc.

How much RAM do you have, and what is a typical project size for you?

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

I think you had the right idea in paragraph two.

Nick Asked Another (another) area that I’m currently trying to separate out is encoding vs display, and I think I might be confusing the two. I fact, isn’t it that the two exponents assume the same footage coming in, only adjusting at the display for different viewing environments?

Not sure I understand your question.

Think of Display Color Management the same as “Proof Colors” in Photoshop.

As to your display:

1) Unless your monitor has internal LUTs, you “calibrate it” using the display’s contrast and color sliders, while using an Xrite i1 Display Pro and appropriate software. Let’s assume your calibration target is sRGB. If it is calibrated perfectly this means that linear data from the graphics card is displayed with an sRGB monitor gamma (approx 2.2).

2) In ADDITION to calibrating, you also create a system display profile for this monitor (again using the i1 Display Pro). This profile tells the system how to send a particular color to your display. If your display is perfectly calibrates, then the transfer curve in the profile is a straight line. But more commonly it will be curved a bit to correct for deltaE errors in the calibration.

3) Now in Display Color Management, AE will convert the workspace to the display space by setting the signal gamma as: <workspace gamma> / <display gamma>
So if the workspace gamma is linear (1.0) and the monitor is gamma 2.2, then that’s 1/2.2 i.e. 0.4545

4) If you “simulate output”, then in addition to applying the 0.4545 curve, an additional curve adjustment is added to emulate a device that is different that your display. If your display were calibrated to “HDTV”, and you selected the “HDTV” simulation, you would see no difference with simulation on or off.

None of this display stuff has any bearing on the output encoding. this is just how the workspace gets presented to the graphics card and monitor. Your output encoding is determined by the codec and output module. settings.

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

Hi Nick,

Nick Said: “Why is it doing that?” A: ………..THIS is de facto how things are”, it’s only working to rules that are a user’s responsibility to set.

Yes, but unfortunately, Adobe does NOT choose the “correct” way to do things for all workflow or environments. I’ve been burned by Adobe’s idea of how something should be transformed in colorspace more than once, and it’s led me to a workflow that does not “rely” on what Adobe thinks or wants be to adhere to.

Even some of the ICC profiles that Adobe ships with AE are technically wrong, or labeled in a way that leads to confusion. And woe betide anyone that actually follows some of Adobe’s documentation on color management as it is rife with “doing things the wrong way”, at least for feature film and TV work in a Hollywood workflow.

Nick Said: So the output profile is actually a final burnt in transform that occurs upon render, is this right? In the case of 2.2/ 2.4 gamma, you could use the output module to adjust the gamma for ‘typical’ HDTV/ sRGB targets?

Yes, if you are using color management in the output profile, it will perform a final transform based on the output profile selected. But a common error is using the wrong output profile. For instance, Rec709 defines a signal gamma that refers to the source (i.e. camera) and this is the profile that should be used for output. Rec 1886 defines the monitor/display value, which is different than Rec709 — but the monitor defined in 1886 EXPECTS to see video that is USING the Rec709 curve. So if you choose the 1886 curve as an output profile (sometimes called the Rec709 Display or Rec709 2.4 gamma) THIS IS WRONG.

The AE Output Module behaves relative to the current Working Space. If your working space is elle_v4_sRGB, 8 bit, and not linear, and you output to an 8 bit video container using the t=same profile as the working space profile, the output will have the same RGB values — and in fact the RGB values will be the same if you select “Preserve RGB” in this one instance.

But instead, to take advantage of the best that AE has to offer, we more typically want to working in a linearized workspace, and this means we have to have some way to accurately display what we are working on. Most of the time this means using color management via “Display Color Management”.

But this ALSO means that you need to plan your workflow, including choosing Interpretation Rules, working chromacities, and output transforms. Adobe’s implementation of linearized working space is half-baked, with badly written documentation, misleading dialogs or labels in the UI, and inconsistent results depending on a few factors.

For instance, in linearized mode:

• 1)

Text anti-aliasing will work differently, resulting in a substantial change from expected behavior, and often requiring additional anti-aliasing added.

[Andrew Somers]

Hi Nick, thank you, lemme address your questions:

NICK ASKED: Q1. Upon export, the output profile defaults to my sRGB working space. Why does the same file import with profile Rec.709 Gamma 2.4?

Before I answer first let me mention that:

1) sRGB and Rec709 are THE SAME except for the gamma (transfer curve). sRGB and Rec709 have the same chromacity, meaning the same color primaries and the same white point.

2) Video is not “color managed” in Quicktime, though sometimes there is a tag relating to a gamma curve.Video is not color managed outside of the AE application, you can’t embed a profile in a Quicktime for instance. “Color Management” means that you use an ICC color profile to convert from one color space, into another colorspace, using either an intermediate “connection” color space (usually CIE XYZ), or a “device link” profile. With “video”, you encode using a set of specifications with the intent to play via a display that is calibrated to a related set of specifications. This is a “calibrated color workflow” not a “color managed workflow”.

3) When you output from After Effects, the output color profile you used is NOT, repeat NOT associated with the Quicktime file. What AE puts into the Quicktime headers (called ATOMs) is based on the codec, resolution, and file type, and may or may not include a tag for a specific gamma. But not your method of output. If you want to see what the Atoms are, you can download the free AtomInspector.app from apple.

4) Now to answer YOUR question: Files are imported based on the “Interpretation Rules.txt” file, found in ~/Library/Preferences/Adobe/After Effects (and there is also the file “AE_MediaCoreQTCodecRulesCS6.xml” which is in application support that deals partly with how video is tagged on output).

In Interpretation Rules you can tell AE how a particular file type is to be imported and what profile to interpret it as, for RGB type files (DNX 444 should be settable here).

When it comes to Y’CbCr type video files (like ProRes 422) things are less flexible, as this kind of file “apparently” can’t be handled directly by the Adobe CMM and ICC profiles, so AE has a separate way to handle these, and it is much less flexible than the Interpretation Rules file, it’s the “AE_MediaCoreQTCodecRulesCS6.xml” for AE and the “MediaCoreQTCodecRulesCS6.xml” for AME and Premier. Both files are located in the ~/Library/ApplicationSupport/Adobe/Common — there is very little documentation on this file unfortunately, and it seems to have no control on clor SPACES, just color ENCODING.

••• So to answer your questions the long way around: The file is output without “relevant” colorspace information if you are outputting to Quicktime, and it is IMPORTED based on the interpretation rules file. If you are doing DNX 444, then you should be able to set your Interpretation Rules to use the profile you want on import.

NICK ASKED: Q2. What should I expect to see from the same DnX 444 clip on the same workstation inside Adobe Premiere? What about if an export (again DnX 444) from Premiere made its way back to AE?

There are no “interpretation rules” for PP or AME as far as I know, their interpretations all happen in the “MediaCoreQTCodecRulesCS6.xml” file.

NICK ASKED: Q3. On other flavours of DnX, why is it again that the input profiles of such flavours aren’t adjustable? Is it as this page of the Adobe forums suggests?

So this is all about the difference between RGB and Y’CbCr/Yuv etc.
As I mentioned above, Y’CbCr color encoding cannot use the regular color management engine. It’s important to remember that Y’CbCr is not a colorspace, it is a color encoding type, and it is used mainly to reduce the amount of data in a file.

ICC based color management is all about converting from one color space or gamut to a different space or gamut. While I am not an engineer for Adobe, I am guessing that they are not able to use the regular ICC profile based CMM for Y’CbCr encodings, and had to write separate code for this file type. 422 video is not only Y’CbCr but the color data is ALSO down sampled so the color information is at a lower resolution than the luminance. I don’t believe this is not something that ICC color management is designed to deal with — and actually I don’t think you’d want to. IMO ICC based color management is actually a BAD FIT for working with film and video. I no longer use color management in the output modules, leaving them to “Preserve RGB” and then using LUTs such as those from OpencolorIO on the output comp to get into the delivery container.

BUT FOR YOU: Get into the Interpretation Rules.txt file and set the rules you need for you DNx 444 files.

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

Dave said: Wow, that’s way above my pay grade. Nobody in my building has Mocha Pro.

PRO is definitely worth it, just the “object removal” feature alone is with it. With object removal you can do things like set extensions. Here’s a tutorial David Shorey did just for that: https://www.mochapromagic.com/archives/84

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

In other words don’t do it all in a single line – use multiple lines, and set the lines on the grid that are farther away from camera to a thinner stroke. There might me a little tiny “jog” where each line joins, but shouldn’t be too obtrusive.

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

Hi Kevin,

I finally had a spare moment to look at this on my main workstation (24 vcore MacPro SSD boot, with 3 wide gamut monitors connected to an NVIDIA GeForce GTX 780 6GB).

The monitors are two Samsung 245T on left and right, and the center is an NEC PA271W.

With both Quicktime player 7 and 10.4, the video play solid smooth in the NEC and on the RIGHT Samsung. The LEFT Samsung however will occasionally judder, mainly on the FIRST cat (adult calico).

However there ARE setting in Quicktime 7 PROPERTIES that will make this video judder even on the NEC.

If you set for instance “Transparency” to COMPOSITION,, the video studders on all monitors/video ports.

As such I suggest talking a look at the properties editor for the QT mov. And also take a look in this thread of my response to Steve Bentley regarding setting monitors for smoothest playback.

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

Steve Said: It could also be a gfx card issue. We’ve got an AE setup with a GTX 970 and can’t find a way to make it playback smooth in AE even though it plays the rendered QT just fine on the same screen.

Hey Steve,

The problem with nVidia GTX cards is that they are optimized for gamers and not filmmakers. Games want cards that do in excess of 60fps so they have the best response rates. But cards that run this fast rendering a game may not have its settings set optimally for 24 or 23.976 playback.

You can adjust these setting using various utilities.

For OS X there is SwitchResX.app

For Windoze there is nVidia-Inspector

See also: https://www.reddit.com/r/leagueoflegends/comments/7cmdzx/smooth_60fps_guide_nvidia_gpu/

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com

[Andrew Somers]

You could stagger the lines so that closer lines uses a thiner stroke.

Andrew Somers
VFX & Title Supervisor
https://www.GeneralTitles.com