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3.OpenCV image write

OpenCV image write

cv2.imwrite('yahboom1.jpg', img)

The first parameter is the name of the saved file, and the second parameter is the saved image.

Next, we will demonstrate the method of image writing. First, we need to read an image yahboom.jpg, then, write it to yahboom1.jpg.

Code:

import cv2
# Up to 4 parameters, first parameter:Read file, second parameter: Parsing format analysis, third parameter: Data decoding, fourth parameter: Data loading
img = cv2.imread('yahboom.jpg', 1)
# cv2.imshow('yahboom, img)  
cv2.imwrite('yahboom1.jpg', img) # 1 name 2 data

Note: The cv2.imshow ('yahboom, img) function in jupyLab cannot be executed. If you need to use this sentence to display the read image, you need to execute the python file through the command on the Raspberry Pi graphical interface.

Command: python3 XX.py

#bgr8 to jpeg format
import enum
import cv2
 
def bgr8_to_jpeg(value, quality=75):
return bytes(cv2.imencode('.jpg', value)[1])

import ipywidgets.widgets as widgets
 
image_widget = widgets.Image(format='jpg', width=320, height=240)
display(image_widget)
img = cv2.imread('yahboom1.jpg',1)
image_widget.value = bgr8_to_jpeg(img)

OpenCV image read and display

OpenCV image quality