Hi,
is it possible to add auto converting all RGB colors assigned to vector objects from MS Office to CMYK colors in LibreOffice?
Or maybe a choice if someone wants to do it or not?
Converting from one colour space to another colour space is not always possible. This can be done only if the colour lies in the common intersection of both gamuts. Any colour outside the intersection will be approximated and not translated faithfully. There are several ways to achieve this approximation and depends on author/artist’s intent.
Usually, colour space conversion is a matter of a specialised library integrated in the OS. Such a library is very tricky to implement due to calibration issues. It is then much better to let the OS do the job and LO uses the OS services.
Note you can use CMYK colour definition in LO by choosing Custom Color in colour picker.
Yes, I am aware that RGB color space is bigger than the CMYK. I am 25+ in DTP business and I want this feature added because of customers who send me MS Office files which are in RGB color space.
I would like when resaving Word file in LibreOffice as .ODT file, to be prepared for importing in some DTP app.
You can’t say that RGB is larger than CMYK. It largely depends on the primaries. For instance, it is well known that the LCD-screen gamut is ridiculously smaller than sRGB.
I gave a look at the OASIS Open Document Format v1.3 where it is explicitly stated (para 18.3.9) that colours are encoded as RGB with notation #rrggbb, implying that there are only 8 bits par channel and no alpha channel.
Consequently, conversion to CMYK must be done in your DTP program.
So, if it can’t be done in LO, it can’t be done in any DTP app. Same rules are for both.
Not sure same rules apply. DTP apps have special provisions for colour separation. That’s a very long time I last worked with Quark XPress. I kind of remember we could choose the type of colorspace, at least CMYK and Pantone which are references in print industry (even if screen rendering was awful – and technology was then CRT which is way better than today LCD).
Color definitions and colors spaces conversions are same for any application that uses colors. The difference is only if they use plain formulas to convert color spaces or take in consideration color destinations (FOGRA, US Web coated SWAP…).
LibreOffice has no colour management, let the DTP program do the conversion.
Scribus Colour Management setup
https://wiki.scribus.net/canvas/Convert_all_colors_to_CMYK
Or try GIMP but it doesn’t have native support but apparently can be added with plugin, CMYK color mode Gimp 2.10