set -e
mkdir frames42x42
mkdir frames42x42masked

ffmpeg -i input.mp4 -an -vf crop=272:272,scale=42:42,fps=6 42x42_fps6_muted.mp4
ffmpeg -i 42x42_fps6_muted.mp4 frames42x42/%05d.png 

python3 mask.py
ffmpeg -y -framerate 6 -i frames42x42masked/%05d.png 42x42.apng
mv 42x42.apng 42x42.png

from PIL import Image

w = 42
h = 42
x0 = (w - 1) / 2
y0 = (h - 1) / 2

R = min(h, w) / 2 - 1

def crop_to_circle(im):
    for x in range(w):
        for y in range(h):
            dist = ((x0 - x) ** 2 + (y0 - y) ** 2) ** 0.5
            if dist > R:
                im.putpixel((x, y), (0, 0, 0, 0))

n = 32450
for i in range(1, n + 1):
    print('\r%05d/%05d' % (i, n), end='')
    im = Image.open('frames%dx%d/%05d.png' % (w, h, i)).convert('RGBA')
    crop_to_circle(im)
    im.save('frames%dx%dmasked/%05d.png' % (w, h, i))

import cv2
from PIL import Image, ImageDraw
from tqdm import tqdm
import random

target_fps = 6
video = cv2.VideoCapture('./input.mp4')

first42 = None
first100 = None

sequence42 = []
sequence100 = []

mask = Image.new('L', (272, 272), 0)
draw = ImageDraw.Draw(mask)
draw.ellipse((0, 0, 271, 271), fill=255)

frame_count = video.get(cv2.CAP_PROP_FRAME_COUNT)
nth_frame = video.get(cv2.CAP_PROP_FPS) / target_fps
frame_id = 0
frameids = []

while int(frame_id) < frame_count - nth_frame:
    frame_id += nth_frame
    frameids.append(frame_id)

def rand_mod(img):
    for i in range(4):
        width, height = img.size
        random_x = random.randint(0, width - 1)
        random_y = random.randint(0, height - 1)
        random_channel = random.randint(0, 2)

        pixel = list(img.getpixel((random_x, random_y)))
        if pixel[random_channel] < 255:
            pixel[random_channel] += 1
        else:
            pixel[random_channel] -= 1
        img.putpixel((random_x, random_y), tuple(pixel))

for frame_id in tqdm(frameids):
    video.set(cv2.CAP_PROP_POS_FRAMES, int(frame_id))
    ret, frame = video.read()
    if not ret:
        break
    frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)

    img = Image.fromarray(frame)
    cropped = img.crop((104, 0, 376, 272))
    round = Image.composite(cropped, Image.new('RGBA', (272, 272)), mask)

    img100 = round.resize((100, 100))
    img42 = round.resize((42, 42))

    rand_mod(img100)
    rand_mod(img42)

    if first42 is None:
        first100 = img100
        first42 = img42
    else:
        sequence100.append(img100)
        sequence42.append(img42)

    img.close()
    cropped.close()
    round.close()

def save(first, sequence, name):
    first.save(name, optimize=True, compression_level=9, save_all=True,
                     append_images=sequence, loop=0, duration=int(1000 / target_fps))

save(first42, sequence42, '42.png')
save(first100, sequence100, '100.png')