palette.py

# script to get palette of an image (5 main colors)
import sys 
from skimage.io import imread, imshow
from skimage.color import rgb2hsv
from sklearn.cluster import KMeans

# [a] -> [(a, a, a)]
def group(lst, n): 
  for i in range(0, len(lst), n): 
    val = lst[i:i+n]
    if len(val) == n:
      yield tuple(val)

# read image from first argument and convert to HSV
img = rgb2hsv(imread(sys.argv[1]))

# get list of colors
colors = list(group(img.flatten(), 3)) 

# perform KMeans fit
kmeans = KMeans(n_clusters=5).fit(colors)

# cluster centers represent the palette
print(kmeans.cluster_centers_)