Make your sketch using OpenCV in Python— easy project

Let’s do it…

Code for making a sketch using OpenCV…

import cv2
import numpy as np

def sketch(image):
gray = cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
blur_gray = cv2.GaussianBlur(gray,(5,5),900)
edges = cv2.Canny(blur_gray,45,90)
ret,thre = cv2.threshold(edges,70,255,cv2.THRESH_BINARY_INV)
return thre

cam = cv2.VideoCapture(0)

while 1:
ret,frame =
cv2.imshow('Live Sketch', sketch(frame))
if cv2.waitKey(1)==27:
if cv2.waitKey(1)==13:
print('Image Saved!!!')

  • Line 1–2 — Importing required libraries.
  • Line 4–9 — Defining the sketch function. We will use this function to implement sketches using OpenCV.
  • Line 5 — Convert the image from BGR to gray.
  • Line 6 — Gaussian Blur the image, to remove Gaussian Noise.
  • Line 7 — Find edges in the image using Canny Edge Detection.
  • Line 8 — Threshold the image, to convert it to a binary image (just 0 and 255 pixels).
  • Line 9 — Return the thresholded image.
  • Line 11 — Instantiate the camera using cv2.VideoCapture(0). Here 0 means that it will use a webcam.
  • Line 13 — Let’s start the loop.
  • Line 14 — Read the image/frame from the camera.
  • Line 15 — Show the sketch image returned by the sketch function when the current frame is passed into it.
  • Line 16–17 — If someone hits the ESC key, break the code.
  • Line 18–20 — If someone hits ENTER key, save the sketch.
  • Line 22–23 — Close the webcam and destroy all open windows.

Final results…



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