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nconvert 8bit per component

Posted: Tue Dec 01, 2009 4:55 pm
by Maxime000
Hello,
I have some trouble with a batch I use on some TIFF image files that are in CMJK.
When I open the TIFF with XNView there is this alert box saying :
The picture will be converted to RGB with 8bits per component

and the the image is correctly displayed. So far, so good.
But when I run my resizing nconvert command on the TIFF, the resulting image has a very unpleasant blue tint all over the colored pixels.
What parameter should I use with nconvert to run this "8bits per component transformation" on my files? It is apparently a CMJK conversion problem but I can't find the correct way to translate it in RGB with nconvert.

Nconvert is v5.50
XnView is v1.96.5

Re: nconvert 8bit per component

Posted: Tue Dec 01, 2009 5:19 pm
by xnview
On XnView do you use ICC profile?

Re: nconvert 8bit per component

Posted: Wed Dec 02, 2009 7:47 am
by Maxime000
Hi Pierre,
Yes I have "use ICC Embeded profile" enabled and I use the sRGB colorspace in XnView.
If I uncheck "use ICC Embeded profile" the TIFF is loaded with the same bleuish tint I want to avoid.

I guess then that I need to instruct nconvert to use the sRGB colorspace, instead of whatever it uses when it deals with CMJK TIFF files... is there such an option?
(I tried to use "-icc_ie" but the result is still blue, I tried also with "-icc_bcp" but my conversion fails, and I do'nt know how to use the "-icc" option)

Re: nconvert 8bit per component

Posted: Wed Dec 02, 2009 8:19 am
by xnview
You can add -icc (use embedded profile)

Re: nconvert 8bit per component

Posted: Wed Dec 02, 2009 8:47 am
by Maxime000
You can add -icc (use embedded profile)

I tried that and it didn't work either.

Nconvert is still v5.50
XnView is now v1.97

Re: nconvert 8bit per component

Posted: Wed Dec 02, 2009 9:47 am
by xnview
Maxime000 wrote:Nconvert is still v5.50
XnView is now v1.97

Download nconvert 5.54

Re: nconvert 8bit per component

Posted: Wed Dec 02, 2009 11:21 am
by Maxime000
xnview wrote:Download nconvert 5.54

Done. And the result is the same. Still blue. :?

Nconvert is now v5.54
XnView is now v1.97

Re: nconvert 8bit per component

Posted: Wed Dec 02, 2009 5:35 pm
by xnview
Could you send me the file?

Re: nconvert 8bit per component

Posted: Thu Dec 03, 2009 11:27 am
by Maxime000
:arrow: Pm sent.

Re: nconvert 8bit per component

Posted: Fri Jun 24, 2016 1:57 pm
by raauw
Is this problem dealt with? I have the exact same problem. Made a topic about it to. Xn just doens't convert these files right. You can already see it when opening them. some cmyk tints of green,blue,pink fall outside the RGB spectrum and when converting to RGB something goes horribly wrong.

Re: nconvert 8bit per component

Posted: Tue Aug 09, 2016 6:31 am
by DOS386
raauw wrote:Is this problem dealt with? I have the exact same problem.


Can you upload the TIFF causing problems?

The picture will be converted to RGB with 8bits per component


XnView v1.97.1 (LIBFORMAT v5.60) 22/02/2010:
* NConvert support 16bits per component loading (-org_depth)


This doesn't seem to work at all for me (tested with 16-bppc PNG) ... result is very same with and without "-org_depth" ... internal processing seems to be always 8-bit per component. Also NC apparently ignores the "gAMA" and "sRGB" chunks ... it assumes sRGB for both 8-bppc and 16-bppc PNG.

Re: nconvert 8bit per component

Posted: Mon Jun 05, 2017 7:45 am
by nesoor
Did someone find a solution ?
I have the same problem when opening a jpg file.