Tool to decompose an image in print colors. The separation of the CMYK channels (for the 4 ink colors Cyan, Magenta, Yellow and Key for Black) is used to analyze the colors of each part of an image.
CMYK Channels - dCode
Tag(s) : Image Processing
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CMYK Channels
Cyan/Magenta/Yellow/Black Channels Separation
Answers to Questions (FAQ)
What are CMYK channels in an image? (Definition)
In printing, CMYK are the initials of the 4 primary four-color process colors, namely: Cyan, Magenta, Yellow and (K) Black. Any image can be decomposed into 4 superimposable color channels to reform the original image.
How to separate CMYK values of an image?
The image will be analyzed in printing color components (4 layers). There are four main colors when printing: Cyan, Magenta, Yellow and Black.
The result will be returned in grayscale for each color. Between 0 for no color and 1 for pure color.
Example: The dCode logo do not have any Cyan (light blue)
Example: For magenta the C is very visible
Example: The yellow is dominating the whole image
Example: The black draws the contours of the image
In order to accelerate the calculation of channel separation, the image will be resized if it is too large.
How to calculate CMYK values from RGB values?
From RGB values $ R $, $ V $ and $ B $ between $ 0 $ and $ 1 $ (divide by 255 if the values are between 0 and 255)
CMYK values are calculated using formulas:
$$ K = 1-max(R, G, B) \\ C = (1-R-K) / (1-K) \\ M = (1-G-K) / (1-K) \\ J = (1-B-K) / (1-K) $$
Why the letter 'K' in CMYK?
In English, CMYK (instead of CMYB) stands for Cyan, Magenta, Yellow and Black. To not use the B letter for Black (as B stands for Blue in RGB code), term Key is preferred (the black component is often the most important when printing: the key)
Source code
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In a scientific article or book, the recommended bibliographic citation is: CMYK Channels on dCode.fr [online website], retrieved on 2025-04-16,
- Cyan/Magenta/Yellow/Black Channels Separation
- What are Cyan/Magenta/Yellow/Black Channels Separation channels in an image? (Definition)
- How to separate Cyan/Magenta/Yellow/Black Channels Separation values of an image?
- How to calculate Cyan/Magenta/Yellow/Black Channels Separation values from RGB values?
- Why the letter 'K' in Cyan/Magenta/Yellow/Black Channels Separation?
