add palette module

myapp/palette.py

@@ -0,0 +1,30 @@
+import numpy as np
+from PIL import Image
+from sklearn.cluster import KMeans
+
+
+def join_images(a: Image.Image, b: Image.Image):
+    result = Image.new(a.mode, (a.width + b.width, max(a.height, b.height)))
+    result.paste(a)
+    result.paste(b, (a.width, 0))
+
+    return result
+
+
+def generate_palette_image(model: KMeans, size=40):
+    image = Image.new("RGB", (0, size))
+
+    for cluster_center in model.cluster_centers_:
+        color = tuple(map(int, cluster_center))
+        part = Image.new("RGB", (40, 40), color)
+        image = join_images(image, part)
+
+    return image
+
+
+def extract_color_clusters(image_array: np.ndarray):
+    w, h, d = image_array.shape
+    pixels = image_array.reshape(w * h, d)
+    model = KMeans(n_clusters=4).fit(pixels)
+
+    return model