Page 477 - AI Ver 3.0 class 10_Flipbook
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In OpenCV we first need to draw a bounding box around a certain area known as ‘region of interest (ROI)’. After
this we will extract the image of that ROI only which will help us to create a cropped image.
roi = img[135:365,115:350] #img[range of y, range of x]
• Let us now try this in getting the face of the dog:
[1]: import cv2 # import OpenCV
from matplotlib import pyplot as plt # import matplotlib
import numpy as np # import numpy
img = cv2.imread('D:/Flower.jpg')
roi =img[135:365,115:350] #img[range of y, range of x]
plt.imshow(cv2.cvtColor(roi, cv2.COLOR_BGR2RGB))
plt.title('Flower') #Display this title on the top of the image
plt.axis('off')
plt.show()
Shading a Portion of an Image
The pixel value of the image can be changed to shade the image, make it black or white to hide some portion
of the image.
img[200:270,200:275]=[0,0,0] #make black shade in given range
plt.imshow(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))#display image with given shade
[1]: import cv2 # import OpenCV
from matplotlib import pyplot as plt # import matplotlib
import numpy as np # import numpy
img = cv2.imread('D:/Flower.jpg')
img[200:270,200:275]=[0,0,0] #make black shade in given range
plt.imshow(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))#display image with given shade
plt.title('Flower') #Display this title on the top of the image
plt.axis('off')
plt.show()
Advance Python (Practical) 475

