Bug 352796

Summary:	CMYK modeled PDFs display a color shift
Product:	[Applications] okular	Reporter:	Krešimir Čohar <kcohar>
Component:	PDF backend	Assignee:	Okular developers <okular-devel>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	aacid
Priority:	NOR
Version:	0.23.0
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
URL:	http://oi59.tinypic.com/9k410l.jpg
Latest Commit:		Version Fixed In:
Attachments:	an example of the problem using my Histology textbook pdf, in CMYK you can use this pdf to test it out

Description Krešimir Čohar 2015-09-16 12:15:22 UTC

CMYK modeled PDFs display a color shift -- they become slightly more saturated than normal (see included image of Okular vs Google Chrome rendering; Google Chrome renders the colors accurately). The same problem appears in iBooks for iOS.

Reproducible: Always

Steps to Reproduce:
1. Open PDF with CMYK color model. I used my Histology textbook.
2.
3.

Actual Results:  
Everything renders fine except for the colors.

Expected Results:  
Everything should have rendered fine, including the colors. There should be no difference between the colors of a CMYK and RGB color model PDF.

Comment 1 Krešimir Čohar 2015-09-16 12:17:43 UTC

Created attachment 94595 [details]
an example of the problem using my Histology textbook pdf, in CMYK

Comment 2 Albert Astals Cid 2015-09-16 23:02:34 UTC

Need an actual pdf to reproduce (i may also need new eyes since my slight color blindness won't help with this :D but let's worry about that later)

Comment 3 Krešimir Čohar 2015-09-17 00:36:35 UTC

Created attachment 94609 [details]
you can use this pdf to test it out

Comment 4 Albert Astals Cid 2015-09-20 20:50:11 UTC

Could you point me (remember slightly colorblind) in attachment 94595 [details] what is wrong?

Comment 5 Krešimir Čohar 2015-09-21 08:56:36 UTC

there's a shift of blue-violet that's prominently visible in the slides and the lines beneath the slide headings. it would be visible on any color, in any hue/saturation shift.

Comment 6 Albert Astals Cid 2015-09-22 23:03:54 UTC

Now that i realize, sorry but this is not an okular bug, it is a poppler bug.

poppler is the library we use to deal with pdf files, so if the rendering is wrong, it is on their side.

Please report a bug at http://bugs.freedesktop.org/

Comment 7 Krešimir Čohar 2015-09-22 23:05:58 UTC

oh ok will do :D thanks!