OpenCV Exercise

Make sure we are in our home directory

[code lang="bash"]
cd ~
[/code]

[code lang="bash"]

cd ~

[/code]

Create a new directory for this exercise

[code lang="bash"]
mkdir pytest
cd pytest
[/code]

[code lang="bash"]

mkdir pytest

cd pytest

[/code]

Download the image below to this new directory

Copy the following code:

# import the necessary packages

import numpy as np

import cv2

# load the games image

image = cv2.imread("test.png")

# find the red color game in the image

upper = np.array([65, 65, 255])

lower = np.array([0, 0, 200])

mask = cv2.inRange(image, lower, upper)

# find contours in the masked image and keep the largest one

(_, cnts, _) = cv2.findContours(mask.copy(), cv2.RETR_EXTERNAL,

cv2.CHAIN_APPROX_SIMPLE)

c = max(cnts, key=cv2.contourArea)

# approximate the contour

peri = cv2.arcLength(c, True)

approx = cv2.approxPolyDP(c, 0.05 * peri, True)

# draw a green bounding box surrounding the red game

cv2.drawContours(image, [approx], -1, (0, 255, 0), 4)

cv2.imshow("Image", image)

cv2.waitKey(0)

Paste the code into a file called pytest.py

[code lang="bash"]
vi pytest.py
[/code]

[code lang="bash"]

vi pytest.py

[/code]

Paste then save and exit vi

Run the python program

[code lang="python"]
python pytest.py
[/code]

[code lang="python"]

python pytest.py

[/code]

Now it should make a green square around the red logo box.

The exercise is to make it make the square around the blue logo box (middle one).

Email me back the result

OpenCV Simple Exercise