#reTerminal – Installing OpenCV, and using a USB WebCam 🤳

Hi !

Let's start with some posts using reTerminal with a very simple scenario:

Connect a Camera to the device and show the camera feed in reTerminal display

The output is something similar to this one.

And let´s start with the base code to run this, based on my previous posts on OpenCV (see references)

	import os
	import cv2
	import time
	# init camera
	execution_path = os.getcwd()
	camera = cv2.VideoCapture(0)
	while True:
	# Init and FPS process
	start_time = time.time()
	# Grab a single frame of video
	ret, frame = camera.read()
	# calculate FPS >> FPS = 1 / time to process loop
	fpsInfo = "FPS: " + str(1.0 / (time.time() - start_time))
	print(fpsInfo)
	cv2.putText(frame, fpsInfo, (10, 10), cv2.FONT_HERSHEY_SIMPLEX, 0.4, (255, 255, 255), 1)
	# Display the resulting image
	cv2.imshow('Video', frame)
	# Hit 'q' on the keyboard to quit!
	if cv2.waitKey(1) & 0xFF == ord('q'):
	break
	# Release handle to the webcam
	camera.release()
	cv2.destroyAllWindows()

view raw PythonWebCamFeed.py hosted with ❤ by GitHub

The main prerequisite to run this code is to have OpenCV installed. And this is a tricky process in a Raspberry Pi. I used to install all the necessary libraries and apps, and then build OpenCV in my device (see references).

Today I follow these steps to make this happens.

1st I install Virtual Environments to I can work in isolated modes for my tests. Run these scripts

sudo pip3 install virtualenv
virtualenv -p python3 camLabs
source camLabs/bin/activate</pre>

Last line will activate my virtual environment.

Once I'm in the virtual environment, I can install OpenCV with the following command

sudo pip install opencv-contrib-python==4.1.0.25</pre>

And run the quick test to validate the installation.

In the process I learned a couple of lessons about installation with amazing errors like these ones

At the end, the simple command to install OpenCV makes the magic!

References

• SeeedStudio - Getting Started with reTerminal
• Visual Studio Code – 20 lines to display a webcam camera feed with Python using OpenCV
• RaspberryPi – Install OpenCV

Continue reading #reTerminal – Installing OpenCV, and using a USB WebCam 🤳

Comments

[ShinProg (Logan Tann)]

For that length, I'd prefer having the whole post here instead of a link to your blog :(

[El Bruno]

I managed to have the full content sync from my blog to here :D

[El Bruno]

Thanks for the feedback ! I'm using the automated cross-post process. I'll try to ffigure out how to do the full cross-posting, instead of the header.