View Issue Details

IDProjectCategoryView StatusLast Update
0003540ScribusInternalpublic2016-04-13 03:30
ReporterringercAssigned To 
PriorityhighSeverityfeatureReproducibilityalways
Status confirmedResolutionopen 
Platformx86 LinuxOSFedora CoreOS VersionFC5
Product Version1.3 
Target VersionFixed in Version 
Summary0003540: Support explicit greyscale colour space
DescriptionScribus currently supports the /DeviceGrey space though explicit greyscale PDF output, but doesn't seem to offer any way to use /DeviceGrey in CMYK or RGB output.

It may desirable to be able to have explicitly greyscale colours in the picker that are always output as /DeviceGrey no matter what the output target. They'd be guaranteed never to be altered into impure greys during colour management etc.

I know some printers and designers really want to be able to ensure that they use these "pure greys", or have in the past. I still need to look up details, but I think it's worth putting this bug here. If nothing else, it can be determined to be unneccesary and closed as WONTFIX.
Tagscomics, grayscale
Patch

Relationships

has duplicate 0011025 closedjghali Better 1 bit PDF generation 
child of 0004413 acknowledged Metabug: Colors 
child of 0013013 new Metabug: Comics 

Activities

ringerc

2006-04-02 05:46

reporter   ~0009584

Note that I'm really not entirely sure this is necessary. It's posible that simple RGB colours where R=G=B will do, possibly with some logic to always export greyscale colours as /DeviceGrey . Or /DeviceGrey use might just not prove that important. It's worth looking into though.

christoph_s

2006-04-20 14:04

administrator   ~0010178

I absolutely agree. I have already seen greyscale images that have been ruined in the process, especially in digital printing. IMHO, this very desirable.

louisdesjardins

2006-04-20 14:22

developer   ~0010181

Fully agree.

christoph_s

2006-04-21 21:28

administrator   ~0010272

May suggest setting the priority to high? Scribus praises itself for its world class output qualities, and I feel this has to be implemented somewhere on the road to 1.4.

plinnell

2006-04-21 21:42

viewer   ~0010274

+1

we should also add indexed colors too at some point

christoph_s

2006-04-22 00:50

administrator   ~0010285

plinell, don't you think both extentions should be added to the roadmap? These are very important features.

plinnell

2006-04-22 15:45

viewer   ~0010314

added to roadmap

JussiP

2012-08-09 15:17

reporter   ~0028791

Also monochrome color space (that is, 1-bit B&W images) should be supported. They are very important in e.g. comic book work.

JussiP

2012-08-10 10:31

reporter   ~0028799

Here is a more detailed description of how 1 bit images should work when working on comic books. The requirement is that the 1-bit image is line art and the DTP program must preserve all details.

Assume that a 1-bit image is put on top of some other image or element. Further assume that its CMYK values are (c, m, y, k). What needs to go to the printing plate is the value (c, m, y, MAX_K) wherever there are black pixels and (c, m, y, k) for white pixels.

Effectively this is a multiply operation. However it is possible to do this with plain PDF 1.3 without transparency effects. I think the corresponding option in Indesign is "overprint fill" but I'm not entirely sure on that.

The images must _not_ be flattened or converted to CMYK images by Scribus (as currently happens). It is extremely important that the 1-bit image does not go through the RIP's line rasterizer. The only way to ensure that is to write them in the PDF as monochrome images.

Issue History

Date Modified Username Field Change
2006-04-02 02:58 ringerc New Issue
2006-04-02 03:02 ringerc Severity minor => feature
2006-04-02 05:46 ringerc Note Added: 0009584
2006-04-20 14:04 christoph_s Note Added: 0010178
2006-04-20 14:22 louisdesjardins Note Added: 0010181
2006-04-21 21:28 christoph_s Note Added: 0010272
2006-04-21 21:34 mhanski Priority normal => high
2006-04-21 21:42 plinnell Note Added: 0010274
2006-04-21 21:42 plinnell Status new => confirmed
2006-04-22 00:50 christoph_s Note Added: 0010285
2006-04-22 15:45 plinnell Note Added: 0010314
2006-04-22 15:45 plinnell Product Version => 1.3
2006-10-14 22:22 mhanski Relationship added child of 0004413
2012-08-09 15:03 jghali Relationship added has duplicate 0011025
2012-08-09 15:17 JussiP Note Added: 0028791
2012-08-10 10:31 JussiP Note Added: 0028799
2015-04-15 02:30 Kunda Tag Attached: comics
2015-04-15 02:35 Kunda Relationship added child of 0013013
2016-04-04 23:13 Kunda Tag Attached: greyscale
2016-04-13 03:30 Kunda Tag Attached: grayscale
2016-04-13 03:30 Kunda Tag Detached: greyscale