发布于 2015-09-11 16:12:10 | 120 次阅读 | 评论: 0 | 来源: 网络整理
#
# The Python Imaging Library
# $Id$
#
# map CSS3-style colour description strings to RGB
#
# History:
# 2002-10-24 fl Added support for CSS-style color strings
# 2002-12-15 fl Added RGBA support
# 2004-03-27 fl Fixed remaining int() problems for Python 1.5.2
# 2004-07-19 fl Fixed gray/grey spelling issues
# 2009-03-05 fl Fixed rounding error in grayscale calculation
#
# Copyright (c) 2002-2004 by Secret Labs AB
# Copyright (c) 2002-2004 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#
from PIL import Image
import re
[docs]def getrgb(color):
"""
Convert a color string to an RGB tuple. If the string cannot be parsed,
this function raises a :py:exc:`ValueError` exception.
.. versionadded:: 1.1.4
:param color: A color string
:return: ``(red, green, blue[, alpha])``
"""
try:
rgb = colormap[color]
except KeyError:
try:
# fall back on case-insensitive lookup
rgb = colormap[color.lower()]
except KeyError:
rgb = None
# found color in cache
if rgb:
if isinstance(rgb, tuple):
return rgb
colormap[color] = rgb = getrgb(rgb)
return rgb
# check for known string formats
m = re.match("#www$", color)
if m:
return (
int(color[1]*2, 16),
int(color[2]*2, 16),
int(color[3]*2, 16)
)
m = re.match("#wwwwww$", color)
if m:
return (
int(color[1:3], 16),
int(color[3:5], 16),
int(color[5:7], 16)
)
m = re.match("rgb(s*(d+)s*,s*(d+)s*,s*(d+)s*)$", color)
if m:
return (
int(m.group(1)),
int(m.group(2)),
int(m.group(3))
)
m = re.match("rgb(s*(d+)%s*,s*(d+)%s*,s*(d+)%s*)$", color)
if m:
return (
int((int(m.group(1)) * 255) / 100.0 + 0.5),
int((int(m.group(2)) * 255) / 100.0 + 0.5),
int((int(m.group(3)) * 255) / 100.0 + 0.5)
)
m = re.match("hsl(s*(d+)s*,s*(d+)%s*,s*(d+)%s*)$", color)
if m:
from colorsys import hls_to_rgb
rgb = hls_to_rgb(
float(m.group(1)) / 360.0,
float(m.group(3)) / 100.0,
float(m.group(2)) / 100.0,
)
return (
int(rgb[0] * 255 + 0.5),
int(rgb[1] * 255 + 0.5),
int(rgb[2] * 255 + 0.5)
)
m = re.match("rgba(s*(d+)s*,s*(d+)s*,s*(d+)s*,s*(d+)s*)$", color)
if m:
return (
int(m.group(1)),
int(m.group(2)),
int(m.group(3)),
int(m.group(4))
)
raise ValueError("unknown color specifier: %r" % color)
[docs]def getcolor(color, mode):
"""
Same as :py:func:`~PIL.ImageColor.getrgb`, but converts the RGB value to a
greyscale value if the mode is not color or a palette image. If the string
cannot be parsed, this function raises a :py:exc:`ValueError` exception.
.. versionadded:: 1.1.4
:param color: A color string
:return: ``(graylevel [, alpha]) or (red, green, blue[, alpha])``
"""
# same as getrgb, but converts the result to the given mode
color, alpha = getrgb(color), 255
if len(color) == 4:
color, alpha = color[0:3], color[3]
if Image.getmodebase(mode) == "L":
r, g, b = color
color = (r*299 + g*587 + b*114)//1000
if mode[-1] == 'A':
return (color, alpha)
else:
if mode[-1] == 'A':
return color + (alpha,)
return color
colormap = {
# X11 colour table (from "CSS3 module: Color working draft"), with
# gray/grey spelling issues fixed. This is a superset of HTML 4.0
# colour names used in CSS 1.
"aliceblue": "#f0f8ff",
"antiquewhite": "#faebd7",
"aqua": "#00ffff",
"aquamarine": "#7fffd4",
"azure": "#f0ffff",
"beige": "#f5f5dc",
"bisque": "#ffe4c4",
"black": "#000000",
"blanchedalmond": "#ffebcd",
"blue": "#0000ff",
"blueviolet": "#8a2be2",
"brown": "#a52a2a",
"burlywood": "#deb887",
"cadetblue": "#5f9ea0",
"chartreuse": "#7fff00",
"chocolate": "#d2691e",
"coral": "#ff7f50",
"cornflowerblue": "#6495ed",
"cornsilk": "#fff8dc",
"crimson": "#dc143c",
"cyan": "#00ffff",
"darkblue": "#00008b",
"darkcyan": "#008b8b",
"darkgoldenrod": "#b8860b",
"darkgray": "#a9a9a9",
"darkgrey": "#a9a9a9",
"darkgreen": "#006400",
"darkkhaki": "#bdb76b",
"darkmagenta": "#8b008b",
"darkolivegreen": "#556b2f",
"darkorange": "#ff8c00",
"darkorchid": "#9932cc",
"darkred": "#8b0000",
"darksalmon": "#e9967a",
"darkseagreen": "#8fbc8f",
"darkslateblue": "#483d8b",
"darkslategray": "#2f4f4f",
"darkslategrey": "#2f4f4f",
"darkturquoise": "#00ced1",
"darkviolet": "#9400d3",
"deeppink": "#ff1493",
"deepskyblue": "#00bfff",
"dimgray": "#696969",
"dimgrey": "#696969",
"dodgerblue": "#1e90ff",
"firebrick": "#b22222",
"floralwhite": "#fffaf0",
"forestgreen": "#228b22",
"fuchsia": "#ff00ff",
"gainsboro": "#dcdcdc",
"ghostwhite": "#f8f8ff",
"gold": "#ffd700",
"goldenrod": "#daa520",
"gray": "#808080",
"grey": "#808080",
"green": "#008000",
"greenyellow": "#adff2f",
"honeydew": "#f0fff0",
"hotpink": "#ff69b4",
"indianred": "#cd5c5c",
"indigo": "#4b0082",
"ivory": "#fffff0",
"khaki": "#f0e68c",
"lavender": "#e6e6fa",
"lavenderblush": "#fff0f5",
"lawngreen": "#7cfc00",
"lemonchiffon": "#fffacd",
"lightblue": "#add8e6",
"lightcoral": "#f08080",
"lightcyan": "#e0ffff",
"lightgoldenrodyellow": "#fafad2",
"lightgreen": "#90ee90",
"lightgray": "#d3d3d3",
"lightgrey": "#d3d3d3",
"lightpink": "#ffb6c1",
"lightsalmon": "#ffa07a",
"lightseagreen": "#20b2aa",
"lightskyblue": "#87cefa",
"lightslategray": "#778899",
"lightslategrey": "#778899",
"lightsteelblue": "#b0c4de",
"lightyellow": "#ffffe0",
"lime": "#00ff00",
"limegreen": "#32cd32",
"linen": "#faf0e6",
"magenta": "#ff00ff",
"maroon": "#800000",
"mediumaquamarine": "#66cdaa",
"mediumblue": "#0000cd",
"mediumorchid": "#ba55d3",
"mediumpurple": "#9370db",
"mediumseagreen": "#3cb371",
"mediumslateblue": "#7b68ee",
"mediumspringgreen": "#00fa9a",
"mediumturquoise": "#48d1cc",
"mediumvioletred": "#c71585",
"midnightblue": "#191970",
"mintcream": "#f5fffa",
"mistyrose": "#ffe4e1",
"moccasin": "#ffe4b5",
"navajowhite": "#ffdead",
"navy": "#000080",
"oldlace": "#fdf5e6",
"olive": "#808000",
"olivedrab": "#6b8e23",
"orange": "#ffa500",
"orangered": "#ff4500",
"orchid": "#da70d6",
"palegoldenrod": "#eee8aa",
"palegreen": "#98fb98",
"paleturquoise": "#afeeee",
"palevioletred": "#db7093",
"papayawhip": "#ffefd5",
"peachpuff": "#ffdab9",
"peru": "#cd853f",
"pink": "#ffc0cb",
"plum": "#dda0dd",
"powderblue": "#b0e0e6",
"purple": "#800080",
"red": "#ff0000",
"rosybrown": "#bc8f8f",
"royalblue": "#4169e1",
"saddlebrown": "#8b4513",
"salmon": "#fa8072",
"sandybrown": "#f4a460",
"seagreen": "#2e8b57",
"seashell": "#fff5ee",
"sienna": "#a0522d",
"silver": "#c0c0c0",
"skyblue": "#87ceeb",
"slateblue": "#6a5acd",
"slategray": "#708090",
"slategrey": "#708090",
"snow": "#fffafa",
"springgreen": "#00ff7f",
"steelblue": "#4682b4",
"tan": "#d2b48c",
"teal": "#008080",
"thistle": "#d8bfd8",
"tomato": "#ff6347",
"turquoise": "#40e0d0",
"violet": "#ee82ee",
"wheat": "#f5deb3",
"white": "#ffffff",
"whitesmoke": "#f5f5f5",
"yellow": "#ffff00",
"yellowgreen": "#9acd32",
}