HSV Colour Model
Instead of a set of colour primaries, the HSV model uses colour descriptions that have a more intuitive appeal to a user. To give a colour specification, a user selects a spectral colour and the amounts of white and black that are to be added to obtain different shades, tints, and tones. Colour parameters in this model are hue (H), saturation (S), and value (V),
The three-dimensional representation of the HSV model is derived from the RGB cube. If we imagine viewing the cube along the diagonal from the white vertex to the origin (black), we see an outline of the cube that has the hexagon shape. The boundary of the hexagon represents the various hues, and it is used as the top of the HSV hexcone (Figure 3.38). In the hexcone, saturation is measured along a horizontal axis, and value is along a vertical axis through the centre of the hexcone.