nconvert 8bit per component

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Maxime000
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Joined: Thu Dec 04, 2008 8:33 am

nconvert 8bit per component

Post 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
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xnview
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Re: nconvert 8bit per component

Post by xnview »

On XnView do you use ICC profile?
Pierre.
Maxime000
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Joined: Thu Dec 04, 2008 8:33 am

Re: nconvert 8bit per component

Post 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)
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xnview
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Re: nconvert 8bit per component

Post by xnview »

You can add -icc (use embedded profile)
Pierre.
Maxime000
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Re: nconvert 8bit per component

Post 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
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xnview
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Re: nconvert 8bit per component

Post by xnview »

Maxime000 wrote: Nconvert is still v5.50
XnView is now v1.97
Download nconvert 5.54
Pierre.
Maxime000
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Re: nconvert 8bit per component

Post 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
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xnview
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Re: nconvert 8bit per component

Post by xnview »

Could you send me the file?
Pierre.
Maxime000
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Re: nconvert 8bit per component

Post by Maxime000 »

:arrow: Pm sent.
raauw
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Re: nconvert 8bit per component

Post 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.
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DOS386
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Re: nconvert 8bit per component

Post 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.
There is indeed no WinZIP under my rock.
nesoor
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Re: nconvert 8bit per component

Post by nesoor »

Did someone find a solution ?
I have the same problem when opening a jpg file.
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