Image service - apply ICC profiles

ImageMagick for image conversion and image scaling via the image service destination, color profiles can be specified.

Introduction

The following parameters are used for the color management

-intent (Perceptual|Relative|Absolute|Saturation)
They influence the output when a larger color space (RGB) is converted to a smaller scale color space. The asset feature "censhare: xmp.icc.profile" is initially set during metadata mapping. We can reuse it here. There are modes for
"tagged", "untagged" and "simple".
The latter is used when color management in the image service is not switched on. LAB images can not be provided with an ICC color profile. For grayscale images separate color profiles apply. Indexed color images are treated as RGB images.

Example

If you use one of the image modules "Create Additional Image" or "Convert image" a target profile can now be defined for this server actions. Make sure that the target color space matches the selected color profile. Furthermore a conversion from RGB to RGB is also possible. This is clearly visible when converting Adobe RGB to sRGB, Adobe's color model is containing significantly more green and turquoise tones. You will notice a significant difference when converting often oversaturated RGB colors as 100% red. These can only be represented approximately in the CMYK model, because they are beyond its gamut. Such colors look a bit pale in CMYK.

Bright colors in RGB. Before conversion, with settings from RGB to CMYK.

Configuration

The default profiles for RGB, CMYK, and Grayscale must be activated under "Color Management" in the configuration of the image service. The standard uses output intent Perceptual. The ICC color profiles must be made available on the server using the path 'app/services/image/iccprofiles'. When using the service client it needs access to the color profile's <host-preferences-directory>/iccprofiles. When entering the profile name, just type its name with suffix <profilname.icc> as indicated (without path).

After conversion into FOGRA27 IsoCoated