splitImage.py

import sys
import os
from os.path import basename
import cv2
import numpy
import numpy as np

path = "/headless/shared/output.png"
if(len(sys.argv) >= 2):
    path = sys.argv[1]
img = cv2.imread(path)

img_gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
_, img_bin = cv2.threshold(img_gray, 0, 255,
        cv2.THRESH_OTSU)
img_bin = cv2.morphologyEx(img_bin, cv2.MORPH_OPEN,
        numpy.ones((3, 3), dtype=int))

border = img_bin.copy()
border = cv2.erode(border, None)
border = cv2.erode(border, None)
ret, thresh = cv2.threshold(border, 127, 255, 0)

image, contours, hierarchy = cv2.findContours(thresh, 1, 2)

cnt = contours[0]
M = cv2.moments(cnt)
img_rgb = cv2.cvtColor(img_bin, cv2.COLOR_GRAY2BGR)
cv2.drawContours(img_rgb, contours, -1, (0, 0, 255), 2)
cv2.imwrite("dbg."+basename(path)+".png", img_rgb)
big_height, big_width = img_bin.shape
for i, cnt in enumerate(contours):
    x, y, width, height = cv2.boundingRect(cnt)
    if width < 20 or height < 20:
        continue;

    im_clone = np.zeros((big_width, big_height, 3), np.uint8)
    im_clone[:] = (255, 255, 255)

    cv2.drawContours(im_clone, contours, i, (0, 0, 0), 2)
    roi = im_clone[x:x + width, y:y + height]
    name = './roi.'+basename(path) +'.'+str(i)+'.png'

    cv2.imwrite(name, im_clone[y:y + height, x:x + width])

    if os.path.getsize(name) <=0:
    	os.remove(name)