# coding: utf-8
import math
from .generic_utils import handleTypeError
SUPPORTED_COLOR_CODES = ["hex", "rgb", "rgba"]
[docs]def detect_color_code_type(color):
"""Detect Color Code type
Args:
color (tuple / str): color code.
Examples:
>>> from pycharmers.utils import detect_color_code_type
>>> detect_color_code_type("#FFFFFF")
'hex'
>>> detect_color_code_type((255,255,255))
'rgb'
>>> detect_color_code_type((0,0,0,1))
'rgba'
"""
handleTypeError(types=[str, tuple, list], color=color)
if isinstance(color, str):
color_code = "hex"
elif isinstance(color, tuple) or isinstance(color, list):
color_code = {
3: "rgb",
4: "rgba",
}.get(len(color))
return color_code
[docs]def hex2rgb(hex, max_val=1):
"""Convert color code from ``hex`` to ``rgb``"""
return tuple(
[int(hex[-6:][i * 2 : (i + 1) * 2], 16) / 255 * max_val for i in range(3)]
)
[docs]def hex2rgba(hex, max_val=1):
"""Convert color code from ``hex`` to ``rgba``"""
return rgb2rgba(rgb=hex2rgb(hex=hex[-6:], max_val=max_val), max_val=max_val)
[docs]def rgb2hex(rgb, max_val=1):
"""Convert color code from ``rgb`` to ``hex``"""
return "#" + "".join([format(int(255 / max_val * e), "02x") for e in rgb]).upper()
[docs]def rgb2rgba(rgb, max_val=1):
"""Convert color code from ``rgb`` to ``rgba``"""
return (*rgb, 1)
[docs]def rgba2hex(rgba, max_val=1):
"""Convert color code from ``rgba`` to ``hex``"""
return rgb2hex(rgb=rgba2rgb(rgba=rgba, max_val=max_val), max_val=max_val)
[docs]def rgba2rgb(rgba, max_val=1):
"""Convert color code from ``rgba`` to ``rgb``"""
alpha = rgba[-1]
rgb = rgba[:-1]
type_ = int if max_val == 255 else float
# compute the color as alpha against white
return tuple([type_(alpha * e + (1 - alpha) * max_val) for e in rgb])
def _do_nothing(color, max_val=1):
return color
def _toColorCode_create(to_color_code):
def toColorCode(color, max_val=1):
color_code = detect_color_code_type(color=color)
return {
color_code: globals().get(
f"{color_code}2{to_color_code.lower()}", _do_nothing
)
for color_code in SUPPORTED_COLOR_CODES
}.get(color_code)(color, max_val=max_val)
toColorCode.__doc__ = f"""Convert color code to {to_color_code.upper()}
Args:
color (tuple / str): color code.
Examples:
>>> from pycharmers.utils import to{to_color_code.upper()}
>>> to{to_color_code.upper()}("#FFFFFF")
{toColorCode("#FFFFFF")}
>>> to{to_color_code.upper()}((255, 255, 255), max_val=255)
{toColorCode((255, 255, 255), max_val=255)}
>>> to{to_color_code.upper()}((1, 1, 1, 1), max_val=1)
{toColorCode((1, 1, 1, 1), max_val=1)}
"""
return toColorCode
toHEX = _toColorCode_create("hex")
toRGB = _toColorCode_create("rgb")
toRGBA = _toColorCode_create("rgba")
[docs]def choose_text_color(color, max_val=255, is_bgr=False):
"""Select an easy-to-read text color from the given color.
Args:
color (tuple / str) : color code.
max_val (int) : Maximum value.
References:
`WCAG <https://www.w3.org/TR/WCAG20/#relativeluminancede>`_
Examples:
>>> from pycharmers.utils import choose_text_color
>>> from pycharmers.opencv import (cv2BLACK, cv2RED, cv2GREEN, cv2YELLOW, cv2BLUE, cv2MAGENTA, cv2CYAN, cv2WHITE)
>>> colors = locals().copy()
>>> for name,color in colors.items():
... if name.startswith("cv2") and isinstance(color, tuple):
... print(f"{name.lstrip('cv2'):<7}: {str(color):<15} -> {choose_text_color(color=color, max_val=255, is_bgr=True)}")
"""
color_code = detect_color_code_type(color=color)
rgb = toRGB(color=color, max_val=max_val)
if is_bgr:
rgb = rgb[::-1]
def sRGB2RGB(e):
i = e / max_val
return i / 12.92 if i <= 0.03928 else math.pow((i + 0.055) / 1.055, 2.4)
R, G, B = [sRGB2RGB(e) for e in rgb]
# Relative Brightness BackGround.
Lbg = 0.2126 * R + 0.7152 * G + 0.0722 * B
Lw = 1 # Relative Brightness of White
Lb = 0 # Relative Brightness of Black
Cw = (Lw + 0.05) / (Lbg + 0.05)
Cb = (Lbg + 0.05) / (Lb + 0.05)
text_rgb = (0, 0, 0) if Cb > Cw else (max_val, max_val, max_val)
return {"rgb": _do_nothing, "hex": rgb2hex, "rgba": _do_nothing,}.get(
color_code
)(text_rgb, max_val=max_val)
[docs]def generate_color_series(color, variation, diff=10, reverse=False):
"""Generate light and dark color series.
Args:
color (tuple) : Color [0,255]
variation (int) : How many colors to create.
diff (int) : How much to change
reverse (bool) : If ``True``, sort in descending order.
Returns:
colors (list) : colors.
Examples:
>>> from pycharmers.utils import generateLightDarks
>>> generateLightDarks(color=(245,20,25), variation=3, diff=10)
[(235, 10, 15), (245, 20, 25), (255, 30, 35)]
>>> generateLightDarks(color=(245, 20, 25), variation=3, diff=-10)
[(225, 0, 5), (235, 10, 15), (245, 20, 25)]
"""
val = max(color[:3]) if diff > 0 else min(color[:3])
u = 0
for _ in range(variation - 1):
val += diff
if not 255 >= val >= 0:
break
u += 1
return sorted(
[
tuple(
[
max(min(e + diff * (u - v), 255), 0) if i < 3 else e
for i, e in enumerate(color)
]
)
for v in range(variation)
],
reverse=reverse,
)
