Codeblock #1: Lines 1-20# import the necessary packages
import argparse
import imutils
import cv2
 
# construct the argument parser and parse the arguments
ap = argparse.ArgumentParser()
ap.add_argument("-i", "--input", required=True,
	help="path to input image")
ap.add_argument("-o", "--output", required=True,
	help="path to output image")
args = vars(ap.parse_args())
 
# load the input image from disk
image = cv2.imread(args["input"])
 
# convert the image to grayscale, blur it, and threshold it
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
blurred = cv2.GaussianBlur(gray, (5,5), 0)
thresh = cv2.threshold(blurred, 60, 255, cv2.THRESH_BINARY)[1]
# extract contours from the image
cnts = cv2.findContours(thresh.copy(), cv2.RETR_EXTERNAL,
	cv2.CHAIN_APPROX_SIMPLE)
cnts = cnts[0] if imutils.is_cv2() else cnts[1]
 
# loop over the contours and draw them on the input image
for c in cnts:
	cv2.drawContours(image, [c], -1, (0, 0, 255), 2)
 
# display the total number of shapes on the image
text = "I found {} total shapes".format(len(cnts))
cv2.putText(image, text, (10, 20), cv2.FONT_HERSHEY_SIMPLEX, 0.5,
		(0, 0, 255), 2)
 
# write the output image to disk
cv2.imwrite(args["output"], image)
$ python shape_counter.py --input input_01.png --output output_01.png