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(python2.1-lib.info)colorsys

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Conversions between color systems
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Conversion functions between RGB and other color systems.

This manual section was written by David Ascher <da@python.net>.
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.

More information about color spaces can be found at
<http://www.inforamp.net/%7epoynton/ColorFAQ.html>.

The `colorsys' module defines the following functions:

`rgb_to_yiq(r, g, b)'
     Convert the color from RGB coordinates to YIQ coordinates.

`yiq_to_rgb(y, i, q)'
     Convert the color from YIQ coordinates to RGB coordinates.

`rgb_to_hls(r, g, b)'
     Convert the color from RGB coordinates to HLS coordinates.

`hls_to_rgb(h, l, s)'
     Convert the color from HLS coordinates to RGB coordinates.

`rgb_to_hsv(r, g, b)'
     Convert the color from RGB coordinates to HSV coordinates.

`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)