CMYK support?

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Justanick

CMYK support?

Post by Justanick » Wed Jun 04, 2008 5:58 pm

Does Xnview support cmyk ? Can i convert an rgg image > cmyk ???
Tnx a lot.

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xnview
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Re: CMYK

Post by xnview » Wed Jun 04, 2008 7:07 pm

Justanick wrote:Does Xnview support cmyk ? Can i convert an rgg image > cmyk ???
Tnx a lot.
No sorry
Pierre.

roytam1
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Re: CMYK

Post by roytam1 » Wed Oct 15, 2008 7:58 am

xnview wrote:
Justanick wrote:Does Xnview support cmyk ? Can i convert an rgg image > cmyk ???
Tnx a lot.
No sorry
maybe xnview should notify user when opening CMYK images at the moment.

but implementing RGB<->CMYK is not hard at all.
FYI: there's Java reference code:

Code: Select all

 public int[] rgb2cmyk(int R,int G,int B){
  int cmyk []= new int[4];
  cmyk[3]=(int)(Math.min(Math.min(255-R,255-G),255-B)/2.55);//cmykK
  int MyR = (int)(R/2.55);
  int Div = 100-cmyk[3];
  if (Div == 0)Div = 1;
  cmyk[0] = ((100-MyR-cmyk[3])/Div)*100;//cmykC
  int MyG = (int)(G/2.55);
  cmyk[1] = ((100-MyG-cmyk[3])/Div)*100;
  int MyB = (int)(B/2.55);
  cmyk[2] = ((100-MyB-cmyk[3])/Div)*100;
  
  return cmyk;
 }
 public Color cmyk2rgb(int C,int M,int Y,int K){
  float MyC = C/100;
  float MyM = M/100;
  float MyY = Y/100;
  float MyK = K/100;
  
  int R = (int)((1-(MyC*(1-MyK)+MyK))*255);
  int G = (int)((1-(MyM*(1-MyK)+MyK))*255);
  int B = (int)((1-(MyY*(1-MyK)+MyK))*255);
  
  if (R<0) R=0;
  if (G<0) G=0;
  if (B<0>255) R=255;
  if (G>255) G=255;
  if (B>255) B=255;
  
  Color rgb = new Color(R,G,B);
  return rgb;
 }

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Troken
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Re: CMYK

Post by Troken » Thu Oct 16, 2008 7:34 am

roytam1 wrote:... maybe xnview should notify user when opening CMYK images at the moment. ...
Very nice suggestion, I support it! It could be a notifications with a checkbox "Do not show again". This way, new users will be informed and thus reduce confusion about CMYK.

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oops66
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Re: CMYK warning

Post by oops66 » Thu Oct 16, 2008 7:44 am

+1
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JohnFredC
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Post by JohnFredC » Thu Oct 16, 2008 3:55 pm

+1
John

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oops66
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Post by oops66 » Sat Jan 10, 2009 4:58 pm

Done into the V1.96Beta1,
Thanks Pierre
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JohnFredC
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Post by JohnFredC » Sat Jan 10, 2009 5:04 pm

I guess I'm slow. Where is the CMYK conversion?
John

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oops66
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Post by oops66 » Sat Jan 10, 2009 5:50 pm

maybe xnview should notify user when opening CMYK images at the moment.

Right, only this request above is done into V1.96, not the conversion.
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Dstruct
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Re: CMYK

Post by Dstruct » Thu May 14, 2009 3:28 am

xnview wrote:
Justanick wrote:Does Xnview support cmyk ? Can i convert an rgg image > cmyk ???
Tnx a lot.
No sorry
Why not?

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oops66
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Re: CMYK

Post by oops66 » Thu Oct 15, 2009 8:59 am

For Information on my computer: Now the conversion is done with the V1.96.5 version between CMYK (32 bits) and RGB (8 bits per component = 24 bits) plus a xnview window notification.
Thanks Pierre.
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surfacecleanerz
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Re: CMYK support?

Post by surfacecleanerz » Thu Apr 15, 2010 5:26 pm

Hi,
I have some files which I converted from RGB .svg (from inkscape) via KDE Krita to CMYK .pdf, but Xnview tells me they are RGB, which is correct? Is Xnview able to do this conversion also? Where is it to find?

The .pdf files look very different in Xnview than in Adobe Acrobat Reader. I think there is an problem within Xnview! I'm using v1.97.2 under Win XP.

regards,
Stefan

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Re: CMYK support?

Post by xnview » Fri Apr 16, 2010 1:43 pm

XnView can't convert SVG files. CMYK pdf can be different in XnView...
Pierre.

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Re: CMYK support?

Post by surfacecleanerz » Sat Apr 17, 2010 10:04 am

Hi,
ok, but why shows Xnview that the CMYK pdf is RGB?

Should I send you the files?

regards,
Stefan

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Re: CMYK support?

Post by xnview » Mon Apr 19, 2010 8:33 am

Yes please send me it
Pierre.

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