Extract Alpha Channel

Description

Currently only for colorobjects. This function interfaces the .get() method of the object.

Usage

extract_transparency(x, mode='float')

Arguments

x
an object which inherits from colorsspace.colorlib.colorobject or an object of class colorspace.palettes.palette.
modestr
mode of the return. One of "float", "int", or "str".

Return

None, numpy.ndarray: None if the colorobject has no alpha channel, else a numpy.ndarray. The dtype of the array depends on the mode specified.

Examples

from colorspace import *
from colorspace.colorlib import hexcols

# Three colors without alpha
cols1 = ['#023FA5',   '#E2E2E2',   '#8E063B']
# Same colors with transparency 80%, 40%, 80%
cols2 = ['#023FA5CC', '#E2E2E266', '#8E063BCC']

# Convert hex color lists to colorobjects
x1 = hexcols(cols1)
x2 = hexcols(cols2)
# Extract transparency
extract_transparency(x1)
extract_transparency(x2)
array([0.8, 0.4, 0.8])
# Return mode
extract_transparency(x2, mode = "float")
array([0.8, 0.4, 0.8])
extract_transparency(x2, mode = "int")
array([204, 102, 204], dtype=int16)
extract_transparency(x2, mode = "str")
array(['CC', '66', 'CC'], dtype='<U2')
# Extracting transparency from palette objects
from colorspace import palette
p1 = palette(cols1, name = "custom palette 1")
p2 = palette(cols2, name = "custom palette 2")
# No return as colors in palette `p1` have no transparency
extract_transparency(p1, mode = "str")
# Extracting transparency from colors in palette `p2`
extract_transparency(p2, mode = "str")
array(['CC', '66', 'CC'], dtype='<U2')

Raises

  • TypeError: If input object does not inherit from colorobject.
  • TypeError: If 'mode' is not str.
  • ValueError: If 'mode' is not one of the allowed types shown in the arguments description.