Convert RGB images in Black and white… gradually

To convert an image in color into an image in black an white you can use this code, that uses just the PIL module.

from PIL import Image

col = Image.open("man.png")
gray = col.convert('L')
bw = gray.point(lambda x: 0 if x<128 else 255, '1')
bw.save("man_bn.png")

Youn can also get different type of convertions with this code

from PIL import Image
import glob
import os


cnt = 1
pics = glob.glob("*.png")
for n in range(10,255,25):
	for pic in pics:
		col = Image.open(pic)
		gray = col.convert('L')
		bw = gray.point(lambda x: 0 if x<n else 255, '1')
		if cnt < 100:
			pre = 0
		else:
			pre = ""
		bw = bw.convert("RGB", palette=Image.ADAPTIVE, colors=8)
		bw.save(f"{pic[:-4]}{pre}{cnt}.png")
		os.startfile(f"{pic[:-4]}{pre}{cnt}.png")
		cnt += 1

I have re-converted to RGB the files, after the convertion in black and white (you will see the reason below).

This is the result

You could also use this code to create an animation with the changing ‘shadows’ (and this is the reason for I re-converted to RGB the images, before I saved them, otherwise I would have had an error in the following code due to the wrong color palette.

from PIL import Image
import glob
import os

# Create the frames
frames = []
imgs = glob.glob("*.png")
for i in imgs:
    new_frame = Image.open(i)
    frames.append(new_frame)

# Save into a GIF file that loops forever
frames[0].save('png_to_gif.gif', format='GIF',
               append_images=frames[1:],
               save_all=True,
               duration=300, loop=0)

os.startfile("png_to_gif.gif")

This is the output

That is all for now… to be continued?

Published by pythonprogramming