Color Theory in Computer Vision
Last Updated on November 16, 2020 by Editorial Team
Author(s): Akula Hemanth Kumar
Computer Vision
Making computer vision easy with Monk, a low code Deep Learning tool, and a unified wrapper for Computer Vision.

Color Vision

History of Color theory:
Color model from the book “Theory of Colors” by Johann Wolfgang.

RYB colors
Proof as to why RYB was Considered to be primary colors

Trichromatic Theory
- Also known as Young-Helmholtz theory.
Three types of cone photoreceptors
- Short-preferring(Blue)
- Middle-preferring(Green)
- Long-preferring(Red)

RGB Space Spanning

Opponent color theory
- There are colors not directly perceivable in normal lighting conditions.
- The trichromatic theory fails to incorporate these colors.
- The opponent-process works through excitatory and inhibitory responses, with the two components of each mechanism opposing each other.
Gray Scale
- Monochromatic Single Channel
- Pixel values from 0(Black) to 255(White)
- Grayscale images contain only shades of gray.
Use cases
- Less data complexity and storage requirements
- Many applications work well with gray scales. Complex channels are not required.
- Improved computation speeds.
RGB
- The additive color space is based on the RGB color model.
- Three Channels Red, Green, and Blue.
- Used in many image processing and computer vision applications.

Accessing channels of RGB image using OpenCV
https://medium.com/media/0061b5c87860b47bbb1a2d49744f3bf6/href

Additive and Subtractive Color Theory

Convert RGB to CMYK using PIL
https://medium.com/media/19a118f7bb2dd5ec46aa72b59b4923be/href

CIE -LAB
L -Lightness ( Intensity)
a -Green to Magenta
b -Blue to Yellow
Convert RGB to LAB using SkImage
https://medium.com/media/cb962f15bd846c47a5d5211a7c567a25/href

CIE-YCrCb
Y-Luminance , Cr -Red, Cb -Blue
- Resemblance with YUV mode
Convert RGB to YCrCb using SkImage
https://medium.com/media/1008698882bacb1dbfd91d56e48ce8c3/href

CIE-XYZ

Convert RGB to XYZ using SkImage
https://medium.com/media/4ebe5b8a492f56698c70b029d41ac86f/href

HSV

Convert RGB to HSV using Skimage
https://medium.com/media/82c297911f34df38e4f5732f606ce522/href

Other Color Spaces
- Haematoxylin-Eosin-DAB(HED)
- CIE-LCH color space
- YUV color space
- YIQ color space
- Stain color space
- HSL color space
You can find the complete jupyter notebook here.
If you have any questions, you can reach Abhishek. Feel free to reach out to him.
I am extremely passionate about computer vision and deep learning. I am an open-source contributor to Monk Libraries.
You can also see my other writings at:
Color Theory in Computer Vision was originally published in Towards AI on Medium, where people are continuing the conversation by highlighting and responding to this story.
Published via Towards AI