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Need help implementing flood-fill algorithm

So I'm trying to create a flood fill algorithm and I keep getting a recursion error with this. The algorithm seems to have infinite recursion and I cannot pinpoint why. I have looked all over the internet and I cannot find a solution as it seems like my program is correct according to most sources. There seems to be something wrong however. This is the edited version of the code. The error message is still maximum recursions.

Can I get some help?

from PIL import Image, ImageTk
from random import *


w= 75
h= w

flood = Image.new("RGB", (w,h), (0,0,0))

x = 0
y = 0
count = 0

colorlist = []
i = 0

while x < w -1:
    y = 0
    while y < h-1:
        r = random()
        if r < .25:
            flood.putpixel((x,y), (0,0,0))
        else:
            flood.putpixel((x,y), (255,255,255))
        y += 1
    x += 1
x = 0
y = 0
while x < w-1:
    y = 0
    while y < h-1:
        r = random()
        if x == 0 or y == 0 or x == w-1 or y ==h-1:
            flood.putpixel((x,y), (0,0,0))
        y += 1
    x += 1


def floodfill(x,y, d,e,f, g,h,i, image, count):
        count+=1
        (a,b,c) = image.getpixel((x,y))
        if (a,b,c) == (255,255,255):
            (j,k,l) = image.getpixel((x-1,y))
            (m,n,o) = image.getpixel((x+1, y))
            (p,q,r) = image.getpixel((x,y-1))
            (s,t,u) = image.getpixel((x,y+1))
        if count > 990:
            return
        if (a,b,c) == (255,255,255):
            image.putpixel((x,y), (g,h,i))
            floodfill(x-1, y, d,e,f, g,h,i, image, count)
            floodfill(x+1, y, d,e,f, g,h,i, image, count)
            floodfill(x, y-1, d,e,f, g,h,i, image, count)
            floodfill(x, y+1, d,e,f, g,h,i, image,count)


floodfill(2,2, 0,0,0,255,0,0,flood, 0)

flood.save("flood.png")
print("done")
like image 902
user1541756 Avatar asked Jul 31 '12 18:07

user1541756


1 Answers

This has not been tested but is based mostly off the code you provided. It should work and provides an alternative method of implementing the floodfill algorithm. The function could be more efficient.

import PIL
import random
import collections

WHITE = 255, 255, 255
BLACK = 0, 0, 0
RED = 255, 0, 0

def main(width, height):
    flood = PIL.Image.new('RGB', (width, height), BLACK)
    # Create randomly generated walls
    for x in range(width):
        for y in range(height):
            flood.putpixel((x, y), BLACK if random.random() < 0.15 else WHITE)
    # Create borders
    for x in range(width):
        for y in range(height):
            if x in {0, width - 1} or y in {0, height - 1}:
                flood.putpixel((x, y), BLACK)
    floodfill(50, 25, RED, image)
    # Save image
    image.save('flood.png')

def floodfill(x, y, color, image):
    # if starting color is different from desired color
    #     create a queue of pixels that need to be changed
    #     while there are pixels that need their color changed
    #         change the color of the pixel to what is desired
    #         for each pixel surrounding the curren pixel
    #             if the new pixel has the same color as the starting pixel
    #                 record that its color needs to be changed
    source = image.getpixel((x, y))
    if source != color:
        pixels = collections.deque[(x, y)]
        while pixels:
            x, y = place = pixels.popleft()
            image.putpixel(place, color)
            for x_offset in -1, 1:
                x_offset += x
                for y_offset in -1, 1:
                    y_offset += y
                    new_place = x_offset, y_offset
                    if image.getpixel(new_place) == source:
                        pixels.append(new_place)

if __name__ == '__main__':
    main(100, 50)
like image 181
Noctis Skytower Avatar answered Nov 11 '22 16:11

Noctis Skytower