21.7. colorsys — Conversions between color systems

Source code: Lib/colorsys.py

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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.

也參考

More information about color spaces can be found at https://www.poynton.com/ColorFAQ.html and https://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(0.2, 0.4, 0.4)
(0.5, 0.5, 0.4)
>>> colorsys.hsv_to_rgb(0.5, 0.5, 0.4)
(0.2, 0.4, 0.4)