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The contents of the CMY color model page were merged into CMYK color model on December 2022. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT ( talk) 16:30, 16 January 2022 (UTC)
Adopted orphan redirects for searching: CMYK colour model
Can you convert the following RGB coordinates to CMYK??
Color RGB CMYK Gray 128 128 128 Black 0 0 0 White 255 255 255 Red 255 0 128 Orange 255 83 0 Yellow 255 255 0 Lime 83 255 0 Green 0 255 128 Sea blue 0 172 255 Blue 0 0 255 Purple 172 0 255
66.32.71.96 02:21, 2 Apr 2004 (UTC)
Note: (or note to self :-P ) we need an RGB -> CMYK conversion formula, like on HSV color space , that'd be handy. Kim Bruning 12:38, 3 Apr 2004 (UTC)
Okay, let's snarf some formulas off of : http://www.easyrgb.com/math.php?MATH=M12#text12
(mathematics isn't copyrightable AFAIK, and I'll be rewriting anyway :-) )
and then rewrite them to 1 form:
// RGB -> CMY //RGB values = From 0 to 255 // CMY values = from 0 to 255 C = 255 - R M = 255 - G Y = 255 - B //CMY values = From 0 to 255 // and CMY-> CMYK var_K = 1 if ( C < var_K ) var_K = C if ( M < var_K ) var_K = M if ( Y < var_K ) var_K = Y C = ( C - var_K ) / ( 1 - var_K ) M = ( M - var_K ) / ( 1 - var_K ) Y = ( Y - var_K ) / ( 1 - var_K ) K = var_K
Okay, so we'd better write that out tidily :-)
so let's see
finally:
for:
we can simply do:
Okay, as a sucky biologist, my math sucks. Can a real mathematician look this over before adding it to the main article? Else I'll add it in a week or so.
Note that I really don't like the float inbetween step, and it's not really nescesary :-)
Kim Bruning 13:21, 3 Apr 2004 (UTC)
Oh heck, let's be bold and add it, some mathematician will just come along and simplify the float step I'm sure :-)
Kim Bruning 13:27, 3 Apr 2004 (UTC)
Ugh, I think I made some slight errors converting from algorithm to formula. Um I'll leave as is for now, some mathematician can pick up the pieces :-/ Sorry! Kim Bruning 13:32, 3 Apr 2004 (UTC)
Thanks, looks tidier at least! On computers, CYMK is usually represented in 32 bits (4 bytes: C, M , Y, K), so each C, M, Y, K value is an integer from 0 to 255, and not a floating point value from 0 to 1 as was stated on the referenced webpage. Cutting out the floating point values would improve the formula further. (something to sort out in my copious free time :-) Kim Bruning 14:26, 3 Apr 2004 (UTC)
Wow! This formula is really easy to use too! :-) I'm sure there's a way to skip the float phase , but this is nice :-)
Hmm, note I was doing mental arithmetic, so values are rounded off. Kim Bruning 21:48, 3 Apr 2004 (UTC)
okay, one example for 66.32.123.29, though really wikipedia isn't for this. Note that your value for red is really weird?
We're using "red, green blue" so:
tell you what, let's find blue in CMYK
so we do:
Which I happen to know is the right value for blue. :-)
Doesn't anyone think this page should be made more simpler so people can understand or add more explanations to the algorithm-ishs given in the end? My thought since I still do not understand how. -- WB 02:30, Mar 18, 2005 (UTC)
It seems to me that the lack of reversibility in RGB to CMYK to RGB conversions isn't an issue which should prevent presentation of an algorithm. Such an algorithm is a necessity in many applications; for example, rendering an RGB-based image into CMYK inks on paper. CoyneT 00:54, 12 Apr 2005 (UTC)
I added a "citation needed" for the abbreviation. I see a slow edit war on this. There are opinions about what K stands for, and opinions have no place in Wikipedia. Where there is controversy, what is needed is a reference. And it needs to be a good one, not just some other web site based on someone else's opinions. Ideally, a link to an academic article that mentions both opinions, and goes back to the early literature. Until we have a reference, please do not remove the citation needed flag just because you believe you know what it stands for!! — Preceding unsigned comment added by 86.128.65.46 ( talk) 09:42, 13 November 2019 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
I propose merging CMY color model to CMYK color model. The two concepts are almost entirely parallel, and the only differences between them are best covered in a section that directly contrasts the two. In fact, there is NO information in CMY that doesn't already exist in CMYK. The CMY redirected to CMYK until 2019 when a 1 month old account un-redirected it (then appeared to have some edit wars in other color model articles). Curran919 ( talk) 20:06, 13 November 2022 (UTC)
This article is written in American English, which has its own spelling conventions (color, defense, traveled) and some terms that are used in it may be different or absent from other varieties of English. According to the relevant style guide, this should not be changed without broad consensus. |
This
level-4 vital article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||
|
|
||
This page has archives. Sections older than 180 days may be automatically archived by Lowercase sigmabot III when more than 6 sections are present. |
The contents of the CMY color model page were merged into CMYK color model on December 2022. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Peer reviewers: Williamsrs.
Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT ( talk) 16:30, 16 January 2022 (UTC)
Adopted orphan redirects for searching: CMYK colour model
Can you convert the following RGB coordinates to CMYK??
Color RGB CMYK Gray 128 128 128 Black 0 0 0 White 255 255 255 Red 255 0 128 Orange 255 83 0 Yellow 255 255 0 Lime 83 255 0 Green 0 255 128 Sea blue 0 172 255 Blue 0 0 255 Purple 172 0 255
66.32.71.96 02:21, 2 Apr 2004 (UTC)
Note: (or note to self :-P ) we need an RGB -> CMYK conversion formula, like on HSV color space , that'd be handy. Kim Bruning 12:38, 3 Apr 2004 (UTC)
Okay, let's snarf some formulas off of : http://www.easyrgb.com/math.php?MATH=M12#text12
(mathematics isn't copyrightable AFAIK, and I'll be rewriting anyway :-) )
and then rewrite them to 1 form:
// RGB -> CMY //RGB values = From 0 to 255 // CMY values = from 0 to 255 C = 255 - R M = 255 - G Y = 255 - B //CMY values = From 0 to 255 // and CMY-> CMYK var_K = 1 if ( C < var_K ) var_K = C if ( M < var_K ) var_K = M if ( Y < var_K ) var_K = Y C = ( C - var_K ) / ( 1 - var_K ) M = ( M - var_K ) / ( 1 - var_K ) Y = ( Y - var_K ) / ( 1 - var_K ) K = var_K
Okay, so we'd better write that out tidily :-)
so let's see
finally:
for:
we can simply do:
Okay, as a sucky biologist, my math sucks. Can a real mathematician look this over before adding it to the main article? Else I'll add it in a week or so.
Note that I really don't like the float inbetween step, and it's not really nescesary :-)
Kim Bruning 13:21, 3 Apr 2004 (UTC)
Oh heck, let's be bold and add it, some mathematician will just come along and simplify the float step I'm sure :-)
Kim Bruning 13:27, 3 Apr 2004 (UTC)
Ugh, I think I made some slight errors converting from algorithm to formula. Um I'll leave as is for now, some mathematician can pick up the pieces :-/ Sorry! Kim Bruning 13:32, 3 Apr 2004 (UTC)
Thanks, looks tidier at least! On computers, CYMK is usually represented in 32 bits (4 bytes: C, M , Y, K), so each C, M, Y, K value is an integer from 0 to 255, and not a floating point value from 0 to 1 as was stated on the referenced webpage. Cutting out the floating point values would improve the formula further. (something to sort out in my copious free time :-) Kim Bruning 14:26, 3 Apr 2004 (UTC)
Wow! This formula is really easy to use too! :-) I'm sure there's a way to skip the float phase , but this is nice :-)
Hmm, note I was doing mental arithmetic, so values are rounded off. Kim Bruning 21:48, 3 Apr 2004 (UTC)
okay, one example for 66.32.123.29, though really wikipedia isn't for this. Note that your value for red is really weird?
We're using "red, green blue" so:
tell you what, let's find blue in CMYK
so we do:
Which I happen to know is the right value for blue. :-)
Doesn't anyone think this page should be made more simpler so people can understand or add more explanations to the algorithm-ishs given in the end? My thought since I still do not understand how. -- WB 02:30, Mar 18, 2005 (UTC)
It seems to me that the lack of reversibility in RGB to CMYK to RGB conversions isn't an issue which should prevent presentation of an algorithm. Such an algorithm is a necessity in many applications; for example, rendering an RGB-based image into CMYK inks on paper. CoyneT 00:54, 12 Apr 2005 (UTC)
I added a "citation needed" for the abbreviation. I see a slow edit war on this. There are opinions about what K stands for, and opinions have no place in Wikipedia. Where there is controversy, what is needed is a reference. And it needs to be a good one, not just some other web site based on someone else's opinions. Ideally, a link to an academic article that mentions both opinions, and goes back to the early literature. Until we have a reference, please do not remove the citation needed flag just because you believe you know what it stands for!! — Preceding unsigned comment added by 86.128.65.46 ( talk) 09:42, 13 November 2019 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
I propose merging CMY color model to CMYK color model. The two concepts are almost entirely parallel, and the only differences between them are best covered in a section that directly contrasts the two. In fact, there is NO information in CMY that doesn't already exist in CMYK. The CMY redirected to CMYK until 2019 when a 1 month old account un-redirected it (then appeared to have some edit wars in other color model articles). Curran919 ( talk) 20:06, 13 November 2022 (UTC)