21.3. colorsys — Conversions between color systems

The colorsys module defines bidirectional conversions of color values between colors expressed in the RGB (Red Green Blue) color space used in computer monitors and three other coordinate systems: YIQ, HLS (Hue Lightness Saturation) and HSV (Hue Saturation Value). Coordinates in all of these color spaces are floating point values. In the YIQ space, the Y coordinate is between 0 and 1, but the I and Q coordinates can be positive or negative. In all other spaces, the coordinates are all between 0 and 1.

See also:

More information about color spaces can be found at http://www.poynton.com/ColorFAQ.html and http://www.cambridgeincolour.com/tutorials/color-spaces.htm.

The colorsys module defines the following functions:

colorsys.rgb_to_yiq(r, g, b)

Convert the color from RGB coordinates to YIQ coordinates.

colorsys.yiq_to_rgb(y, i, q)

Convert the color from YIQ coordinates to RGB coordinates.

colorsys.rgb_to_hls(r, g, b)

Convert the color from RGB coordinates to HLS coordinates.

colorsys.hls_to_rgb(h, l, s)

Convert the color from HLS coordinates to RGB coordinates.

colorsys.rgb_to_hsv(r, g, b)

Convert the color from RGB coordinates to HSV coordinates.

colorsys.hsv_to_rgb(h, s, v)

Convert the color from HSV coordinates to RGB coordinates.

Example:

>>> import colorsys
>>> colorsys.rgb_to_hsv(.3, .4, .2)
(0.25, 0.5, 0.4)
>>> colorsys.hsv_to_rgb(0.25, 0.5, 0.4)
(0.3, 0.4, 0.2)