A tiny python script 🐍 to extract color palettes 🎨 from any image.

palette.md

Palette

A tiny python script to extract color palettes from any image.

Original script available in rebelot/kanagawa.nvim.

Usage

$ python palette.py --help
usage: palette.py [-h] [-n N] [-r R] [-o] img out

positional arguments:
  img
  out

optional arguments:
  -h, --help  show this help message and exit
  -n N        The number of colors for the palette
  -r R        Rescale factor
  -o

Related

1. How to retrieve all the images from a website
2. How to find the main colours in an image
3. The incredibly challenging task of sorting colours

palette.py

#!/usr/bin/env python

"""
A tiny python script to extract color palettes from any image.
"""

import argparse
import colorsys

import matplotlib.pyplot as plt
import numpy as np
from skimage import color, io
from skimage.transform import rescale
from sklearn.cluster import KMeans


def palette(img, n=10, r=1, o=False):
    img = img[:, :, (0, 1, 2)]
    img = rescale(img, (r, r, 1), anti_aliasing=True)
    lab = color.rgb2lab(img).reshape(-1, 3)
    km = KMeans(n_clusters=n, random_state=0).fit(lab)
    cc = km.cluster_centers_.reshape(-1, 1, 3).transpose((1, 0, 2))

    if o:
        rgb_x = color.lab2rgb(cc)
        initial_colors = list(rgb_x[0])
        initial_colors.sort(key=lambda c: colorsys.rgb_to_hsv(*c))

        return np.asarray([initial_colors])

    return color.lab2rgb(cc)

def p2h(p):
    r, g, b = np.round(p).astype(int)
    return f"#{r:02X}{g:02X}{b:02X}"


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("img")
    parser.add_argument("out")
    parser.add_argument("-n", default=10, type=int, help="The number of colors for the palette")
    parser.add_argument("-r", default=1, type=float, help="Rescale factor")
    parser.add_argument("-o", default=False, action='store_true')
    args = parser.parse_args()
    img = io.imread(args.img)
    p = palette(img, n=args.n, r=args.r, o=args.o)
    h = [p2h(rgb * 255) for rgb in p[0]]
    ax = plt.axes()
    ax.imshow(img)
    ax.set_axis_off()
    axin = ax.inset_axes([0.2, 0.2, 0.6, 0.2])
    axin.set_axis_off()
    axin.imshow(p, aspect="auto")
    plt.savefig(args.out, dpi=800, pad_inches=0, bbox_inches="tight")
    print("\n".join(h))


if __name__ == "__main__":
    main()