#!/usr/bin/env python
#-*- coding:utf-8 -*-

import sys
import numpy as np
from scipy.ndimage import imread, zoom
from matplotlib import pyplot as plt

sys.path.insert(0, '/home/sebastiaan/Tmp/texture/scikit-image/')

from skimage.measure import block_reduce

im = imread('4.png', flatten=True)
im = im != 255

for z in np.arange(1000,1,-1):

    print 'Downsample by %d' % z
    im2 = block_reduce(im, (z,z), func=np.min)
    if True not in im2:
        continue
    l = np.where(im2 == 1)
    row = l[0][0]
    col = l[1][0]

    minY = int(row*z)
    maxY = int((row+1)*z)
    minX = int(col*z)
    maxX = int((col+1)*z)
    surface = (maxX-minX)*(maxY-minY)

    print '(%d, %d) -> (%d, %d), surface = %d' % (minX, minY, maxX, maxY, \
        surface)

    plt.subplot(211)
    plt.imshow(im)
    plt.axhline(minY, color='white')
    plt.axhline(maxY, color='white')
    plt.axvline(minX, color='white')
    plt.axvline(maxX, color='white')
    plt.subplot(212)
    plt.imshow(im2)
    plt.show()

    break