SOLVED: Barcode created in RGB, how to make CMYK?

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dougray

I have a colour-managed CMYK document, using Scribus 1.4.5

When I use Scribus' barcode generator, it creates a barcode (object-group)
in RGB colourspace.  So when I export to PDF/X-3 (pdf 1.3), the pre-flight
verifier complains.

Is there a way to convert it to CMYK within Scribus?

I've exported to GIMP, changed colourspace, reimported.   Is there a better
solution?   The GIMP workaround means I get a little aliasing when the
?postscript? objects are digitised, and the export/import/export/import
workflow is daft.

If I must export to change colourspace, is it practical to export/import
as postscript?

thanks in advance

a.l.e

ehm ehm...

i had a look at the way the barcode creator works and i came to the conclusion, that it's not correctly implemented.

it should not provide you with an open choice of rgb colors, but just let you choose among colors that are already defined for the document.
no reason to allow other colors, here.
(most of the time you will want transparent / white and black anyway)

i will open a ticket for it.

now, i see two workarounds for you:

- you work in RGB and use the correct ICC color profile to get scribus to convert the colors to CMYK while exporting to pdf

- after having created the barcode, ungroup it, select all the vertical bars (not the background, not the numbers below) and set their background color to a CMYK color (probably black), select the numbers below the bars and set their fill to the CMYK color, select the background and delete it or use the right color for it.
(the best way to select the different type of items is to drag select from outside the barcode... easier to show and do, rather than explain...)

have fun
a.l.e

a.l.e

p.s.: just checked: no need for a bug report... in 1.5svn the barcode generator works correctly and already only offers existing colors as a choice

dougray

Thanks for the advice on 1.5svn, and also for thinking through the object-group
construction and solution.

About your first workaround:

Quote from: a.l.e on July 13, 2015, 07:29:14 PM
now, i see two workarounds for you:

- you work in RGB and use the correct ICC color profile to get scribus to convert the colors to CMYK while exporting to pdf

I'm using U.S. Web-coated (SWOP)v2

Wouldn't this conversion happen for the barcode, even when it is the only part of the document that is not CMYK? ... my pdf export was caught with the pre-flight check - was there a way to prevent that, and force conversion?

Thanks again

dougray

THANK YOU!!!!   ungroup, drag-select the whole thing, then just
   edit -> change colours  [RGB black -> CMYK black]
   edit -> change colours [RGB white -> CMYK white]
...

Quote from: a.l.e on July 13, 2015, 07:29:14 PM
- after having created the barcode, ungroup it, select all the vertical bars (not the background, not the numbers below) and set their background color to a CMYK color (probably black), select the numbers below the bars and set their fill to the CMYK color, select the background and delete it or use the right color for it.
(the best way to select the different type of items is to drag select from outside the barcode... easier to show and do, rather than explain...)

I couldn't have thought this through without your help... thanks again!