FAQ

Questions about this project

Where can I ask how to use it?

Use Help forum in Sourceforge.JP. Note that we cannot accept general questions about computers or GIMP.

Where can I report a bug or request?

Check Ticket page in Sourceforge.JP. If no tickets similar to the content you would like to report have been registered, register it as a new ticket. Tickets are mainly written in Japanese, but you can register it in English.

If you waver whether to register or not, try to ask another person about it in Developers forum.

Common questions to each plug-in

Plug-ins cannot be chosen from the dialog.

To choose a plug-in from the list, the profile should be installed in the predetermined locations. Profile Choice button (or dialog) searches and lists the following locations.

Locations for storing personal profiles
All systems	$HOME/.color/icc
Mac OS X	Home/Library/ColorSync/Profiles
Locations for storing system profiles
Except Windows	/usr/share/color/icc
Windows	%SYSTEMROOT%\System32\spool\drivers\color %COMMONPROGRAMFILES%\Adobe\Color\Profiles
Mac OS X	/Library/ColorSync/Profiles /Library/Application Support/Adobe/Color/Profiles

To choose a profile which is not located in the predetermined location, drag and drop an icon of the profile from explorer or Nautilus to Profile Choice button. Or, input the full path of the profile, and click OK.

If you cannot choose a profile which is properly installed, the type of the profile may not be appropriate. For instance, you cannot choose a CMYK profile at the place which a RGB profile is required.

Questions about the separate plug-in

After the installation of separate plug-in, will GIMP support CMYK?

No. CMYK data is interpreted and processed only within separate plug-in. From a GIMP's viewpoint, it is not recognized that CMYK data is processed.

Can I correct colors after the separation?

Edit C/M/Y/K layers created by the color separation (for pseudo-composite, layer masks). To check the result after editing, you need to execute the Proof function.

Which image formats can separate plug-in export to?

It supports export to TIFF (uncompressed, LZW), JPEG (image quality preceded, compressibility preceded) and PSD (uncompressed, PackBits compressed).

*As for Version 0.5.4 or earlier, only uncompressed TIFF file is exported.

I would like to convert an image created by another application. In this case, should I start GIMP?

Because separate is a plug-in, it cannot be run separately unlike ordinary applications. Therefore, you should start GIMP to perform conversion.

If you would like only to perform conversion, ImageMagick, tifficc, or jpegicc commands will process more efficiently.

Can I save CMYK images directly, instead of color separation and then exporting?

Impossible. Instead, you can automate it through a script. Refer to "Qexport" sample script. (Of course, you can use it without modification.)

I cannot proof or export after color separation.

Separate plug-in discriminates processing object using the layer name. Therefore, if you change layer names after the color separation, you cannot proof or export them.

Questions about icc_colorspace plug-in

Color space assignation and conversion seems to be similar to GIMP's default functionality. What is the difference?

The followings are different:

• Selection method of profile is common to separate plug-in.
• GIMP default dialog displays, even for images without profiles, the profile of RGB workspace (RGB profile specified by Preferences) as the current profile. However, dialogues with icc_colorspace plug-in displays "Unknown (image has no profiles)".
• You can remove profiles that have already been assigned.
• When converting an image with an intent of "Absolute colorimetric", you can assign it so that the results is closer to those by Photoshop CS2 or later.

What is an abstract profile?

According to ICC, an abstract profile is explained as follows:

Abstract profiles allow you to perform custom image effects, such as applying a particular 'look' to a series of images. Such a profile allows you to define CIELAB (or CIEXYZ) values as both input and output. Thus you can algorithmically define colour changes of whatever type you like and produce the LUT that achieves that. A small number of colour management applications support the creation and or use of abstract profiles.

For full details of the structure, required tags and processing model, see the ICC profile specification.

How can I get an abstract profile?

Samples are included in a ZIP file of Separate+. Moreover, not so many are pre-installed in Mac OS X. However, basically you will create it for yourself, depending on its use and aim for you.

It is difficult to create an abstract profile from scratch because tools are not available. However, you can modify an existing profile to some extent using ICC Profile Inspector.