Generate and show a palette from the current image, video or camera

palettegen.py

from PIL import Image, ImageDraw
import cv2
import numpy as np
import os
import sys

if len(sys.argv) < 2:
	print("Needs file path ")
	sys.exit(1)

fn = sys.argv[1]

if fn == "0":
	fn = 0
else:
	if not os.path.exists(fn):
		print("Invalid path")
		sys.exit(1)

cap = cv2.VideoCapture(fn)

while True:
	ret, frame = cap.read()

	rgbimg = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
	img = Image.fromarray(rgbimg)

	if fn != 0:
		img = img.resize((img.width//2, img.height//2))

	pal = img.convert('P', palette=Image.ADAPTIVE, colors=6)
	pal.putalpha(0)
	# pal.show()
	colors = pal.getcolors(16*10**5)
	colors = [c[1][:3] for c in colors]

	colors = sorted(colors)

	palheight = int(img.height*0.1)
	palwidth = img.width

	palimg = Image.new("RGB", (palwidth, palheight), "#000000")

	draw = ImageDraw.Draw(palimg)
	x = y = 0
	shift = palwidth//len(colors)
	for c in colors:
		draw.rectangle([x,y, x+shift, y+palheight], fill=c)
		x+= shift

	# palimg.show()
	
	newimg = Image.new("RGB", (img.width, img.height+palheight), "#000000")
	newimg.paste(img, (0,0))
	newimg.paste(palimg, (0, img.height))

	cimg = cv2.cvtColor(np.array(newimg), cv2.COLOR_RGB2BGR)

	cv2.imshow("Palette Gen", cimg)
	# break
	if cv2.waitKey(1) == 27:
		break

cap.release()
cv2.destroyAllWindows()