5.Open Source CV pixel operation

For pixel operations, we can change any position to a new pixel color. Here we first read the image, and then assign an area to white.

The code was run on jupyterlab

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import cv2

img = cv2.imread('yahboom.jpg',1)

(b,g,r) = img[100,100]

print(b,g,r)# bgr

#10 100 --- 110 100

i=j=0

for j in range(1,500):

     img[i,j] = (255,255,255)

     for i in range(1,500):

         img[i,j] = (255,255,255)

 

#cv2.imshow('image',img)

#cv2.waitKey(0) #1000 ms

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#bgr8 to jpeg format

import enum

import cv2

def bgr8_to_jpeg(value, quality=75):

     return bytes(cv2.imencode('.jpg', value)[1])

Use JupyterLab to display before and after image comparison:

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import ipywidgets.widgets as widgets

image_widget1 = widgets.Image(format='jpg', )

image_widget2 = widgets.Image(format='jpg', )

\# create a horizontal box container to place the image widget next to each other

image_container = widgets.HBox([image_widget1, image_widget2])

\# display the container in this cell's output

display(image_container)

img1 = cv2.imread('yahboom.jpg',1)

image_widget1.value = bgr8_to_jpeg(img1) #Original

image_widget2.value = bgr8_to_jpeg(img) #After pixel operation