HSV model depends upon the human perception, and if you don't know what it is, we can start from RGB model.
The left figure shows a RGB cube. If we look at this cube from the white vertex to black vertex angle, we get a Hexagon in which all the six colors(3 RGB colour + 3 CMY Transclusion
Why do printers use the CMY color model instead of RGB?
I have always heard a saying that the three primary colors of light are red, green and blue, and the three primary colors of paint are red, yellow ... color) from that cube's vertex have different angles, and they are seperated each by 60 degrees. We can also twist the hexagon a bit to get a RGB-CMY hue circle. This is what we always saw as the pure colour top layer of a HSV cone.
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HUE represents the angle of rotation around the vertical axis, it describes pure color, range \([0, 360^{\circ}]\) Saturation is how far away from the vertical axis, it describes how much a pure color is diluted by mixing white color, range \([0, 100\%]\). Value is indeed from the vertical(V) axis, it decides the brightness of the color, range \([0, 1]\), V = 0 means black color and V = 1 means white color. |
Note: just to clarify
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HSV(for hue, saturation, value) and HSB (for hue, saturation, brightnessOMG brightness 和 lightness 有个鬼区别啊!!) are the same thing. HSL(hue,saturation, Lightness/Luminosity/Luminance) and HSI (Hue, Saturation, Intensity) are the same thing. But HSV/HSB \(\neq\) HSL/HSI. |