$100 to the hacker/graphic pro that can convert RGB to CMYK!

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dcoppert

$100 to the hacker/graphic pro that can convert RGB to CMYK!

Post by dcoppert »

Hi, I have a few files that need to be converted to a print ready format, and I can't for the life of me figure this out in a timely manner (I own a start-up business).

My files were created in the freeware design program,Inkscape, and I can export them to a PNG image file. The problem is PNG files only support RGB color and I need them to be converted into CMYK color for printing.

I have a logo and two business cards (front and back) that need to be converted so that the coloring comes out as it should.

I am hoping someone would like to do this for $100, I can pay you via paypal. I can email the files, either in the svg or png format, I just need to know what you need in order to get the print ready resolution and color.

Please email me at giveplustake@yahoo.com if this is a piece of cake for you and you want the $100 for a bit of expertise.

Oh, and my business website is http://www.giveplustake.com--just so you know I am a serious business owner with a printing snafu...

Thanks,
Dora Copperthite
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magick
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Re: $100 to the hacker/graphic pro that can convert RGB to C

Post by magick »

Ensure your version of ImageMagick includes LCMS support. Type
  • identify -list configure
Is lcms associated with the DELEGATES tag? If not, download and install the LCMS delegate library and its development package and then reconfigure, rebuild, and reinstall ImageMagick.

Now all you need is an input and output profile. Your command will look something like this:
  • convert image.jpg -profile sRGB.icc -profile CMYK.icc image.tif
We convert to TIFF because PNG does not support CMYK. You could also convert to JPEG since it does support CMYK.
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fmw42
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Re: $100 to the hacker/graphic pro that can convert RGB to C

Post by fmw42 »

do you have to keep them as png. you can easily convert them to jpg or tiff in cmyk format

input: zelda3.png
Image

convert zelda3.png -profile Profiles/sRGB.icc -profile Profiles/CMYK.icc zelda3_cmyk.jpg
Image

zelda3_cmyk.jpg
Image: zelda3_cmyk.jpg
Format: JPEG (Joint Photographic Experts Group JFIF format)
Class: DirectClass
Geometry: 128x128+0+0
Resolution: 72x72
Print size: 1.77778x1.77778
Units: PixelsPerInch
Type: ColorSeparation
Endianess: Undefined
Colorspace: CMYK
Depth: 8-bit
Channel depth:
cyan: 8-bit
magenta: 8-bit
yellow: 8-bit
black: 8-bit
Channel statistics:
Cyan:
min: 0 (0)
max: 213 (0.835294)
mean: 65.2887 (0.256034)
standard deviation: 43.5856 (0.170924)
kurtosis: -0.128428
skewness: 0.607757
Magenta:
min: 0 (0)
max: 250 (0.980392)
mean: 111.45 (0.437059)
standard deviation: 69.9743 (0.274409)
kurtosis: -0.910377
skewness: 0.449587
Yellow:
min: 0 (0)
max: 255 (1)
mean: 114.051 (0.447259)
standard deviation: 70.338 (0.275835)
kurtosis: -1.05266
skewness: 0.317875
Black:
min: 0 (0)
max: 222 (0.870588)
mean: 22.3588 (0.0876817)
standard deviation: 38.1746 (0.149704)
kurtosis: 6.0648
skewness: 2.44863



convert zelda3.png -profile Profiles/sRGB.icc -profile Profiles/CMYK.icc zelda3_cmyk.tiff
Image

identify zelda3_cmyk.tiff
Image: zelda3_cmyk.tiff
Format: TIFF (Tagged Image File Format)
Class: DirectClass
Geometry: 128x128+0+0
Resolution: 72x72
Print size: 1.77778x1.77778
Units: Undefined
Type: ColorSeparation
Base type: ColorSeparation
Endianess: MSB
Colorspace: CMYK
Depth: 16-bit
Channel depth:
cyan: 16-bit
magenta: 16-bit
yellow: 16-bit
black: 16-bit
Channel statistics:
Cyan:
min: 37 (0.000564584)
max: 53825 (0.821317)
mean: 16651.3 (0.254083)
standard deviation: 11192.3 (0.170783)
kurtosis: -0.140368
skewness: 0.604717
Magenta:
min: 151 (0.00230411)
max: 63409 (0.967559)
mean: 28514.4 (0.435102)
standard deviation: 17973.9 (0.274264)
kurtosis: -0.91036
skewness: 0.450782
Yellow:
min: 121 (0.00184634)
max: 64681 (0.986969)
mean: 29184.7 (0.44533)
standard deviation: 18059 (0.275563)
kurtosis: -1.05478
skewness: 0.318034
Black:
min: 0 (0)
max: 56395 (0.860533)
mean: 5597.74 (0.085416)
standard deviation: 9807.49 (0.149653)
kurtosis: 6.03559
skewness: 2.44502


Post a link to one of your images and we can try it.

Or email it directly to me at fmw at alink dot net
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Re: $100 to the hacker/graphic pro that can convert RGB to C

Post by snibgo »

As magick hints, to ensure "the coloring comes out as it should", you MUST know the profile of the output devices. Ask your printer for the profile, which will be a .icc or .icm file.
snibgo's IM pages: im.snibgo.com
dcoppert

Re: $100 to the hacker/graphic pro that can convert RGB to C

Post by dcoppert »

Thanks for all your replies! I really appreciate it! This is pretty specialized knowledge, outside the normal realm for printers and graphic designers and I just kept hitting a wall.

fmw42: They don't need to be a PNG, that is just how I can export them from inkscape. I don't know how to get them from the RGB PNG to a JPeg or Tiff that is CMYK. I am not sure if it is as easy as opening the PNG image in a program that can export as a Jpeg or Tiff or if there is an intermediate step that must take place to get the colors within the document converted to CMYK and then exporting as a Tiff or JPeg.

Magick: So far I have not downloaded Imagemagick, I just found that you all were somehow getting this job done--but trust me, I am so not knowledgeable about all of this. I didn't know if I should just issue a cry for help or if I could reasonably expect to figure it out within a couple of hours starting from my place of roughly 0 understanding. It looked pretty techie around here...and I saw code was being used...so I issued the cry for help.

Snibgo: Even if I get the colors to them in a CMYK friendly file, is it necessary for me to know that?

Dora
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Re: $100 to the hacker/graphic pro that can convert RGB to C

Post by snibgo »

Inkscape creates SVG or PNG, but nothing else.

Printers use different inks and papers. The conversion to CMYK should take account of this. (One paper/ink combination might need less magenta ink and more black to get the same result as another paper/ink combination.) The information about these requirements comes in the form of an "icc" or "icm" profile file. If your printer knows what she is doing, just say you need the "ICC" or "ICM" file they will use for your business cards.

Supply that to us (or email it to fmw42), and we can do the conversion.

Failing that, we can use a generic profile that will be approximately correct for any paper and ink.
snibgo's IM pages: im.snibgo.com
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