Basic operations in opencv: and or not, XOR and adding watermark (implemented in Python)

List of articles

• • 1. Non operation of image
  • 2. And operation of image
  • 3. To perform or operate on images
  • 4. Exclusive or operation
  • 5. Add watermark

1. Non operation of image

def FEI():
# Create a picture of the same size
npimg = np.ones(shape=(450,450), dtype=np.uint8)
npimg[100:300,100:300]=255
dst=cv2.bitwise_not(src=npimg)
cv2.imshow('npimg',npimg)
cv2.imshow('dst',dst)
cv2.waitKey(0)
cv2.destroyAllWindows()

2. And operation of image

def And():
# Create a picture of the same size
npimg1 = np.ones(shape=(450,450), dtype=np.uint8)
npimg1[100:300,100:300]=255
npimg2 = np.ones(shape=(450, 450), dtype=np.uint8)
npimg2[50:150, 50:150] = 255
dst=cv2.bitwise_and(src1=npimg1,src2=npimg2)
cv2.imshow('npimg1', npimg1)
cv2.imshow('npimg2', npimg2)
cv2.imshow('dst',dst)
cv2.waitKey(0)
cv2.destroyAllWindows()

3. To perform or operate on images

def OR():
# Create a picture of the same size
npimg1 = np.ones(shape=(450, 450), dtype=np.uint8)
npimg1[100:300, 100:300] = 255
npimg2 = np.ones(shape=(450, 450), dtype=np.uint8)
npimg2[50:150, 50:150] = 255
dst=cv2.bitwise_or(src1=npimg1,src2=npimg2)
cv2.imshow('npimg1', npimg1)
cv2.imshow('npimg2', npimg2)
cv2.imshow('dst',dst)
cv2.waitKey(0)
cv2.destroyAllWindows()

4. Exclusive or operation

def Exotic():
# Create a picture of the same size
npimg1 = np.ones(shape=(450, 450), dtype=np.uint8)
npimg1[100:300, 100:300] = 255
npimg2 = np.ones(shape=(450, 450), dtype=np.uint8)
npimg2[50:150, 50:150] = 255
dst=cv2.bitwise_xor(src1=npimg1,src2=npimg2)
cv2.imshow('npimg1', npimg1)
cv2.imshow('npimg2', npimg2)
cv2.imshow('dst',dst)
cv2.waitKey(0)
cv2.destroyAllWindows()

5. Add watermark

import os
import cv2
import numpy as np
# Read the picture
img=cv2.imread('images/lenna.png')
img=cv2.resize(src=img,dsize=(450,450))
# establish LOGO
logo=np.zeros(shape=(350,350,3),dtype=np.uint8)
# Create a mask
mask=np.zeros(shape=(350,350),dtype=np.uint8)
# Drawing graphics
logo[100:300,100:300]=[0,255,0]
logo[50:250,50:250]=[0,0,255]
mask[100:300,100:300]=255
mask[50:250,50:250]=255
# Yes mask Inverse
mask_not=cv2.bitwise_not(src=mask)
# Choose an image lenna Add logo
roi=img[0:350,0:350]
#roi And mask_not Conduct “ And ” operation 
temp=cv2.bitwise_and(src1=roi,src2=roi,mask=mask_not)
# superposition
dst=cv2.add(src1=temp,src2=logo)
img[0:350,0:350]=dst
cv2.imshow('img',img)
# cv2.imshow('logo',logo)
# cv2.imshow('mask',mask)
# cv2.imshow('mask_not',mask_not)
# cv2.imshow('temp',temp)
cv2.waitKey(0)
cv2.destroyAllWindows()
if __name__ == '__main__':
print('Pycharm')