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I.2 HSV color system

If you have played around with RGB color sliders, you will have noticed that it is not intuitive to make a chosen color lighter or darker, more saturated or more gray. It would involve changing three sliders. To make it easier to manipulate colors in terms of lightness and saturation, another coordinate system was invented: HSV (hue, saturation, value). Those terms can be made clear best by looking at the color sliders in Figure I.1a. Hue (running from 0° to 360°) gives you the full spectrum of saturated colors. Saturation (from 0 to 1, or 100%) tells you how `full' your color is: reduce it to zero and you only have gray scales. Value (from 0 to 1, or 100%) will bring you from black to a fully saturated color. Note that ``value'' is not the same as ``intensity'', or ``lightness'', used in other color geometries. ``Brilliance'' may be the best alternative word to describe ``value''. Apple calls it as ``brightness'', and hence refers to HSB for this color space.

Want more chartreuse or chocolate? You can specify them in GMT as 90-1-1 and 25-0.86-0.82, respectively.


next up previous contents index
Next: I.3 The color cube Up: I. Color Space: The Previous: I.1 RGB color system   Contents   Index
Paul Wessel 2009-09-20