[Python] Invert image color

• Mark

import sys
ros_path = '/opt/ros/kinetic/lib/python2.7/dist-packages'

if ros_path in sys.path:
    sys.path.remove(ros_path)

import cv2
import numpy as np

img = cv2.imread("/home/seivl/for_code/2.png",1)  

# kernel = np.ones((3,3),np.uint8)  
# img = cv2.dilate(img,kernel,iterations = 1)

cha=img.shape
height,width,deep=cha
dst=np.zeros((height,width,3),np.uint8)
for i in range(height):  
    for j in range(width):
        b,g,r=img[i,j]
        # print(b,g,r)
        # dst[i,j]=(255-b,255-g,255-r)
        # if b == 48 and g == 48 and r == 48:
        if b == 0 and g == 0 and r == 0:
        # if b == 0 and g == 0 and r == 0:
            dst[i,j]=(255,255,255)
        elif b == 128 and g == 128 and r == 128:
            dst[i,j]=(0,0,0)
        else:
            dst[i,j]=b,g,r
        #     # dst[i,j]=(0,255,0)
        #     dst[i,j]=(0,0,255)
cv2.imshow('img',img)
cv2.imshow('dst',dst) 
cv2.imwrite("/home/seivl/for_code/2_1.png",dst) 

cv2.waitKey(1000000)