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RGB png to CMKY pdf conversion help

Posted: 2014-01-15T13:35:21-07:00
by M1C4HTRON13
I have an RGB png 6969x4843 300dpi
I need to convert it to a CMYK pdf with as little quality loss as possible.

Can you help me

Re: RGB png to CMKY pdf conversion help

Posted: 2014-01-15T16:31:55-07:00
by fmw42
convert image.png -colorspace CMYK image.pdf

or better color quality, by using profiles

convert image.png -profile /path2profiles/USWebCoatedSWOP.icc image.pdf

But, you are just putting a pdf wrapper around a raster image. No quality will be lost, since png is lossless. But you may still have to specify a density when reading the pdf, since pdf format has no true resolution other than the pixels imbedded in it.

You may already have this profile on your system with IM, but if not search the web for it.

see
http://www.imagemagick.org/Usage/formats/#profiles

Re: RGB png to CMKY pdf conversion help

Posted: 2014-01-16T09:37:35-07:00
by M1C4HTRON13
fmw42 wrote:convert image.png -colorspace CMYK image.pdf

or better color quality, by using profiles

convert image.png -profile /path2profiles/USWebCoatedSWOP.icc image.pdf

But, you are just putting a pdf wrapper around a raster image. No quality will be lost, since png is lossless. But you may still have to specify a density when reading the pdf, since pdf format has no true resolution other than the pixels imbedded in it.

You may already have this profile on your system with IM, but if not search the web for it.

see
http://www.imagemagick.org/Usage/formats/#profiles
Thanks

Re: RGB png to CMKY pdf conversion help

Posted: 2014-01-16T11:41:42-07:00
by fmw42
Correction to my post above:

If the png has a profile, then the following is correct.

Code: Select all

convert image.png -profile /path2profiles/USWebCoatedSWOP.icc image.pdf
If it does not have a profile, then you should assume sRGB and use that profile first.

Code: Select all

convert image.png -profile /path2profiles/sRGB.icc -profile /path2profiles/USWebCoatedSWOP.icc image.pdf