Use dithering
It approximates pixels whose conversion result value cannot be expressed by an 8-bit integer with dithering.
When gradation with banding is generated, use dithering and the problem may be remediated.
*Because this option depends on the function of Little CMS version 1.18, it is not effective in the environment where the Little CMS library of version 1.17 or earlier is installed in.
-Building with the header file of Little CMS version 1.17 or earlier disables the option of "Use dither" on the dialogue.
*Using the header file of version 1.18 or later enables the option choice. In case the version of runtime library is 1.17 or earlier, dithering processing is disabled.
Use dither
It approximates pixels whose conversion result value cannot be expressed by an 8-bit integer with dithering.
When gradation with banding is generated, use dithering and the problem may be remediated.
Rendering intent/Use BPC algorithm
Choose a method of gamut mapping in the convert between the color space of an image and PCS (Lab or XYZ space).
* history.en.html
Version 0.5.7
* Support dithering in "Separate", "Convert colorspace" and "Apply abstract profile"
* separate : Remove a build option which changes "Separate" dialogue by full (pseudo-composite) or light (grayscale)
* separate : Disable "No profiles" option when "Use devicelink profile" is turned on
* separate : Correct reversely placed buttons in the "Export" dialog
* separate : Correct a problem that vertical stretching of "Export" dialogue gives unnecessary space
* icc_colorspace : Enable assignments for Rendering intent at "Apply abstract profile"
* icc_colorspace : Correct a problem that the converting is affected by an area selected
* UI : Make each dialog support Alternative button order
* UI : Set accelerator key at labels on the dialogs
* UI : Configure dialogs as transient (As for X Window environment, plug-in dialogs are associated with document windows)
* IccButton : Consider the encoding of Description profile as the encoding of current locale if it is unknown (neither UTF-16BE nor UTF-8)
* Review arguments of procedures
* Replace sRGB profiles
Release Note (separate-plus - 0.5.7)
Major changes
* Enable to apply dithering processing for a color separation of the separate plug in, color space conversion of the icc_colorspace plug-in and the application of the abstract profile.
* Enable to specify the rendering intent when the application of the abstract profile.
* Fix a problem that a processing result is affected by the selected area at color space conversion of the icc_colorspace plug-in and the application of the abstract profile.
* Perform some adjustment and corrections in UI.
Notes
Limitations about the dithering processing
Because the dithering processing uses a function implemented in Little CMS 1.18 or later, there are the following limitations.
* When you build a plug-in with the 1.17 or earlier version of header file, check boxes in the dialog is disabled and dithering cannot be turned on.
* When you run the plug-in with runtime libraries of 1.17 or earlier, the effect is not provided even if dithering is set to use.
Such a half-finished specification is because of the unavoidable circumstances that Little CMS contains no API that identifies the version of runtime at run time.
Run from script plug-in
Note that the cord correction is required because the number and order of procedure arguments are changed.
The change of sRGB profile
Bundled sRGB profile and the profile included as srgb_profile.h have been sRGB Color Space Profile.icm by Hewlett-Packard until version 0.5.6. However, in 0.5.7, it was replaced with a different profile due to the licensing reason.
Because some specification of new profile is different, it may bring the difference of the result when you convert with "Absolute colorimetric" intent.
For the details, refer to ICC White Paper (PDF) (the bundled profile is compatible with Type 2 of v2 profile written in the second page of the PDF).
