conversions.rgb_cmyk_conversion
===============================

.. py:module:: conversions.rgb_cmyk_conversion


Functions
---------

.. autoapisummary::

   conversions.rgb_cmyk_conversion.rgb_to_cmyk


Module Contents
---------------

.. py:function:: rgb_to_cmyk(r_input: int, g_input: int, b_input: int) -> tuple[int, int, int, int]

   Simple RGB to CMYK conversion. Returns percentages of CMYK paint.
   https://www.programmingalgorithms.com/algorithm/rgb-to-cmyk/

   Note: this is a very popular algorithm that converts colors linearly and gives
   only approximate results. Actual preparation for printing requires advanced color
   conversion considering the color profiles and parameters of the target device.

   >>> rgb_to_cmyk(255, 200, "a")
   Traceback (most recent call last):
       ...
   ValueError: Expected int, found (<class 'int'>, <class 'int'>, <class 'str'>)

   >>> rgb_to_cmyk(255, 255, 999)
   Traceback (most recent call last):
       ...
   ValueError: Expected int of the range 0..255

   >>> rgb_to_cmyk(255, 255, 255)  # white
   (0, 0, 0, 0)

   >>> rgb_to_cmyk(128, 128, 128)  # gray
   (0, 0, 0, 50)

   >>> rgb_to_cmyk(0, 0, 0)    # black
   (0, 0, 0, 100)

   >>> rgb_to_cmyk(255, 0, 0)  # red
   (0, 100, 100, 0)

   >>> rgb_to_cmyk(0, 255, 0)  # green
   (100, 0, 100, 0)

   >>> rgb_to_cmyk(0, 0, 255)    # blue
   (100, 100, 0, 0)