The color profiles are just tags at the head of the file. Some video codecs do not support adding this tag information, others do. As far as I know PhotoJpeg does not. I don't think that the tag embedded by CS4 was passed to or read by other apps. Using the Media Encoder to render your AE projects gives you many more options than using the Render Cue, especially for highly compressed formats. It's the only way you can do multi pass compression in AE.
Any production house, post production house, or broadcaster that wants you to supply color profiles will have that information available. It's just like in the print world. If they use color profiles they will happily give you the specifications. All you have to do is ask. Pros ask. Amateurs assume.
Embedded color profiles do not change the pixel values in the video, they change the way the pixel values are displayed on your display device if your display device supports color management. Most modern displays do. Most, if not all CRT's used for video don't. They have other methods. Before you can trust any color profile you must calibrate your display device. The better the calibration the better chance that the end viewer will have the same experience that you are having.
The embedded gamma tag for QT videos is still a moving target. AE does not add the gamma tag to all quicktime codecs. I don't know if it's a bug or a licensing issue. Color Profiles and LUT's are especially valuable when working with a service provider that is producing your content for distribution. It helps for distribution on the web, but it's far from being worked out to the point where every viewer will have the same experience.
Thank you for these explanations.
I wanted to clarify that my point was not that a video produced by After Effects gets a color profile (I know that usually color profiles are not stored with the video), but it is about how the video is interpreted when imported into After Effects. Suppose I work in a project that has as working space the color profile "Adobe RGB 1998". If the video that I reimport into After Effects was originally produced in AE with Adobe RGB 1998 in the Output Module and then (automatically) interpreted as HDTV when reimported into After Effects, then I obviously get a color shift. This color shift can be avoided if I could assign the color profile "Adobe RGB 1998" in the color management tab of the "Interpret Footage" dialog box when I reimport the video.
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It sounds like you have a pretty good handle on color management. I'll dive a little further into the subject for the readers that don't.
The most important part of color management is knowing what your footage is and making sure that you interpret it that way. The temptation is to interpret the footage as you want it to be. It's the same with Pixel Aspect Ratio. If you have no idea what color profile was used to acquire the footage then the best option is to not color manage that footage.
Here's an example: You've shot with a Sony EX3 and you're going to output to HD Video. You set up your project settings to use HDTV(Rec 709) and turned on Linearize working space because those are the settings for your known output device, a HDTV through a BluRay player. You've also set this same color space for your Main Output Module Color management. You also want to put some video up to YouTube or Vimeo so you set a second Output Module up for that render but you assign sRGB to that module because that's the default color space for web (at least according to most sources).
That leaves the question, what Color Profile do you assign to your EX3 footage? Good question. A Google search isn't much help. You import the footage and find that there's an embedded color profile. You also discover that you can't change it. Life is good. Then, you're supplied a render from C4D or some other source. You import that footage and check the color profile. There may or may not be one embedded. If it's not embedded and locked you can change it. If it says something like sRGB and you can change it, in most cases you shouldn't change it because the guess is probably right. If there is no color profile assigned then you should assume that is correct. You should not assign it to HDTV(Rec 709), your working space, unless you know for sure that the footage was supposed to be color managed.
Did you get that? The Color Profile must be what it is, not what you want it to be for the footage. It's the same with PAR.
I think you get that. What I think you want to know is how to change the interpretation rules text file to make this adjustment automatically. Color profiles are assigned by frame size not codec so I don't think you can do what you want to do. I may be wrong.
A google search for After Effects Color Management brings up several good articles and videos on the subject. I'd suggest you read or watch anything by Stu Maschwitz, Chris and Trish Meyers, Mark Christiansen, and take a look at this introductory video. There's also some good information in the Adobe Help files.
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People are generally using third-party tools such as Gamma Shift Detector and QT Edit to achieve this, as detailed here:
(note: I am the developer of the above two tools)
Thank you Rick for this interesting explanations and the links to articles.
In the past few days I performed a few tests in After Effects and it is interesting that you mention that cameras, like the Sony EX3, allow videos to have embedded color profiles. I am not working myself with cameras but either get footage from the internet or sometimes videos from our video department which produces videos with professional SONY cameras, usually I get them in a matrox mxf format.
As far as my test with After Effects show it is not possible to embed color profiles in the videos rendered with After Effects. Independent of the color profile in the working space and independent from the color profile in the output module I always get the same reaction if I reimport videos rendered by After Effects back to After Effects:
In AE CS5 videos made in the formats Quicktime/PhotoJPEG, Quicktime/H264, H264 main concept, DVCPRO HD 1080p30, F4V are always interpreted as color profile SDTV/HDTV (Rec. 709) Y'CbCr (even if I made them in other color profiles, such as Adobe RGB, Photo RGB, sRGB); and there is no possibility to change this interpretation rule.
In contrast videos made in the formats Quicktime/JPEG2000, Quicktime/Motion JPEG A, Quicktime/Motion JPEG B, Quicktime/MPEG-4, Quicktime/Animation are always interpreted as sRGB (even if if I made them in other color profiles, such as Adobe RGB, Photo RGB, HDTV); only this time I can change the interpretation rule. Therefore if I know for example that if I had selected Photo RGB in the Output module I can change after the reimport the interpretation rule from sRGB to Photo RGB and only then I get again the original colors.
The only exceptions are picture sequences, such as tiff-sequences, where the original color profile is automatically selected in the interpretation of the footage.
Therefore, unfortunately for videos produced by After Effects your advice "If it says something like sRGB and you can change it, in most cases you shouldn't change it because the guess is probably right. If there is no color profile assigned then you should assume that is correct." is not so easy to be applied. You have to know how you did it originally in the Output module and hope that you can change it to the proper color profile, in case that the original color profile in the Output module was different from sRGB and HDTV/SDTV. But it is interesting to hear from you that with cameras there seem to be more possibilities.
For this reason it would be nice if in future versions of After Effects one could change the color profile in the the color management tab of the "Interpret Footage" dialog box also for formats such as Quicktime/PhotoJPEG, Quicktime/H264, H264 main concept, DVCPRO HD 1080p30, F4V.
Of course one can always circumvent shortcomings by using tiff-sequences, QT/jpeg2000, or QT/Animation as formats for storing, which is anyway better for lossless or nearly lossless storing, but the files are then too large and also cannot be played easily with a player.