| \section{\module{colorsys} --- |
| Conversions between color systems} |
| |
| \declaremodule{standard}{colorsys} |
| \modulesynopsis{Conversion functions between RGB and other color systems.} |
| \sectionauthor{David Ascher}{da@python.net} |
| |
| The \module{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 |
| \url{http://www.poynton.com/ColorFAQ.html}. |
| |
| The \module{colorsys} module defines the following functions: |
| |
| \begin{funcdesc}{rgb_to_yiq}{r, g, b} |
| Convert the color from RGB coordinates to YIQ coordinates. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{yiq_to_rgb}{y, i, q} |
| Convert the color from YIQ coordinates to RGB coordinates. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{rgb_to_hls}{r, g, b} |
| Convert the color from RGB coordinates to HLS coordinates. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{hls_to_rgb}{h, l, s} |
| Convert the color from HLS coordinates to RGB coordinates. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{rgb_to_hsv}{r, g, b} |
| Convert the color from RGB coordinates to HSV coordinates. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{hsv_to_rgb}{h, s, v} |
| Convert the color from HSV coordinates to RGB coordinates. |
| \end{funcdesc} |
| |
| Example: |
| |
| \begin{verbatim} |
| >>> 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) |
| \end{verbatim} |