inkstitch/lib/threads/palette.py

86 wiersze
2.7 KiB
Python

# Authors: see git history
#
# Copyright (c) 2010 Authors
# Licensed under the GNU GPL version 3.0 or later. See the file LICENSE for details.
from collections.abc import Set
from colormath.color_conversions import convert_color
from colormath.color_diff import delta_e_cie1994
from colormath.color_objects import LabColor, sRGBColor
from .color import ThreadColor
def compare_thread_colors(color1, color2):
# K_L=2 indicates textiles
return delta_e_cie1994(color1, color2, K_L=2)
class ThreadPalette(Set):
"""Holds a set of ThreadColors all from the same manufacturer."""
def __init__(self, palette_file):
self.threads = dict()
self.parse_palette_file(palette_file)
def parse_palette_file(self, palette_file):
"""Read a GIMP palette file and load thread colors.
Example file:
GIMP Palette
Name: Ink/Stitch: Metro
Columns: 4
# RGB Value Color Name Number
240 186 212 Sugar Pink 1624
237 171 194 Carnatio 1636
"""
with open(palette_file, encoding='utf8') as palette:
line = palette.readline().strip()
if line.lower() != "gimp palette":
raise ValueError("Invalid gimp palette header")
self.name = palette.readline().strip()
if self.name.lower().startswith('name: ink/stitch: '):
self.name = self.name[18:]
# number of columns
palette.readline()
# headers
palette.readline()
for line in palette:
try:
fields = line.split(None, 3)
thread_color = [int(field) for field in fields[:3]]
thread_name, thread_number = fields[3].strip().rsplit(" ", 1)
thread_name = thread_name.strip()
thread = ThreadColor(thread_color, thread_name, thread_number, manufacturer=self.name)
self.threads[thread] = convert_color(sRGBColor(*thread_color, is_upscaled=True), LabColor)
except (ValueError, IndexError):
continue
def __contains__(self, thread):
return thread in self.threads
def __iter__(self):
return iter(self.threads)
def __len__(self):
return len(self.threads)
def nearest_color(self, color):
"""Find the thread in this palette that looks the most like the specified color."""
if isinstance(color, ThreadColor):
color = color.rgb
color = convert_color(sRGBColor(*color, is_upscaled=True), LabColor)
return min(self, key=lambda thread: compare_thread_colors(self.threads[thread], color))