Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: Hermie on September 13, 2006, 03:12:01 pm

Title: Creating matrix profiles with multi-point TRC's
Post by: Hermie on September 13, 2006, 03:12:01 pm
How does one create matrix profiles with multi-point defined TRC's ? E.g. L-Star RGB uses a 256-point curve. Joseph Holmes' profiles use a 1024-point curve.
I know you can use Photoshop to create matrix profiles with gamma-defined curves, or BabelColor that allows for further customization of gamma curves, but is there any standard software that can create these multi-point curves?

Herman
Title: Creating matrix profiles with multi-point TRC's
Post by: TimothyFarrar on September 13, 2006, 08:11:29 pm
Herman, I too would also be interested in such a program. If you find one please post a link here.
Title: Creating matrix profiles with multi-point TRC's
Post by: Stephen Best on September 13, 2006, 09:03:29 pm
Quote
How does one create matrix profiles with multi-point defined TRC's ? E.g. L-Star RGB uses a 256-point curve. Joseph Holmes' profiles use a 1024-point curve.
[a href=\"index.php?act=findpost&pid=76243\"][{POST_SNAPBACK}][/a]

If you're handy with a hex editor, you can just edit the tristimulus values and internal names. This takes less than a minute. Something with the primaries of Beta RGB and Joseph Holmes' new TRC would be interesting. I guess if you're paying for Holmes' profiles in the first instance he wouldn't mind you adapting it for your own use.
Title: Creating matrix profiles with multi-point TRC's
Post by: bjanes on September 14, 2006, 09:46:50 am
Quote
If you're handy with a hex editor, you can just edit the tristimulus values and internal names. This takes less than a minute. Something with the primaries of Beta RGB and Joseph Holmes' new TRC would be interesting. I guess if you're paying for Holmes' profiles in the first instance he wouldn't mind you adapting it for your own use.
[a href=\"index.php?act=findpost&pid=76271\"][{POST_SNAPBACK}][/a]

Steven,

If you are starting out with an L-Star RGB a 256-point curve or Joseph Holmes' profile with a 1024-point curve, you can edit the primaries. However, how do you edit the tone curve itself?

Bill
Title: Creating matrix profiles with multi-point TRC's
Post by: Hermie on September 14, 2006, 03:18:20 pm
By the way, when searching on the subject I came across Argyll CMS.
The Argyll CMS package includes "iccdump.exe" that dumps the contents of an icc profile as readable text.

For example:
The following command-line syntax creates the file output.txt with all 1024 values of rTRC tag of sRGB profile:

iccdump -v3 -t rTRC srgb.icm >output.txt

See http://www.argyllcms.com (http://www.argyllcms.com)

Herman
Title: Creating matrix profiles with multi-point TRC's
Post by: Stephen Best on September 14, 2006, 05:50:10 pm
Quote
Steven,

If you are starting out with an L-Star RGB a 256-point curve or Joseph Holmes' profile with a 1024-point curve, you can edit the primaries. However, how do you edit the tone curve itself?

Bill
[a href=\"index.php?act=findpost&pid=76317\"][{POST_SNAPBACK}][/a]

It's easier to start with the profile with the desired tone curve and just modify the primaries. You'll also need to change the internal names as the profile will show up as a duplicate otherwise. You can use the ColorSync utility on a Mac for the latter.

I'm assuming you're doing this for your own private use only. Matrix profiles are pretty simple but likely still copyrightable etc. You could also ask the original author to make the mods on your behalf, assuming there's a wider demand for the combination of primaries and tone curve in question.
Title: Creating matrix profiles with multi-point TRC's
Post by: Hermie on September 14, 2006, 06:01:42 pm
> Matrix profiles are pretty simple but likely still copyrightable etc.

Right, from Joseph Holmes' website:
"The proprietary tone curve of my profiles is not generic and is therefore protected intellectual property, as is the unique combination of primaries in every published RGB working space. All published profiles are also themselves protected by copyright."
Title: Creating matrix profiles with multi-point TRC's
Post by: bjanes on September 14, 2006, 06:36:18 pm
Quote
I'm assuming you're doing this for your own private use only. Matrix profiles are pretty simple but likely still copyrightable etc. You could also ask the original author to make the mods on your behalf, assuming there's a wider demand for the combination of primaries and tone curve in question.
[a href=\"index.php?act=findpost&pid=76371\"][{POST_SNAPBACK}][/a]

I asked for more information mainly from curiosity. For my own use I'm pretty satisfied with ProPhotoRGB and ACR's adjustment tools.
Title: Creating matrix profiles with multi-point TRC's
Post by: Hermie on January 15, 2007, 05:28:00 pm
Quote
How does one create matrix profiles with multi-point defined TRC's ? E.g. L-Star RGB uses a 256-point curve. Joseph Holmes' profiles use a 1024-point curve.
I know you can use Photoshop to create matrix profiles with gamma-defined curves, or BabelColor that allows for further customization of gamma curves, but is there any standard software that can create these multi-point curves?

Herman
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=76243\")

The latest version of the free "ICC Profile Inspector" (2.3.9) incorporates the ability to modify many of the tag entries in a profile and to export/import TRC's.
See [a href=\"http://www.color.org/profileinspector.html]http://www.color.org/profileinspector.html[/url]

So, using an example export file from "ICC Profile Inspector" and MS Excel you could create a specific multi-point TRC and import it into a profile.

Herman