Code for How to Perform Edge Detection in Python using OpenCV

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edge_detector.py

import cv2
import numpy as np
import matplotlib.pyplot as plt
import sys

# read the image
image = cv2.imread(sys.argv[1])

# convert it to grayscale
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

# show the grayscale image, if you want to show, uncomment 2 below lines
# plt.imshow(gray, cmap="gray")
# plt.show()

# perform the canny edge detector to detect image edges
edges = cv2.Canny(gray, threshold1=30, threshold2=100)

# show the detected edges
plt.imshow(edges, cmap="gray")
plt.show()

live_edge_detector.py

import numpy as np
import cv2

cap = cv2.VideoCapture(0)

while True:
    _, frame = cap.read()
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    edges = cv2.Canny(gray, 30, 100)
    cv2.imshow("edges", edges)
    cv2.imshow("gray", gray)
    if cv2.waitKey(1) == ord("q"):
        break

cap.release()
cv2.destroyAllWindows()