Now thankfully OpenCV or Open computer vision is an API which means that it is a collection of prewritten routines that makes it super much easier to start programming computer vision applications.
Most people will use Python to access the OpenCV routines and this can be done with Python installed on a Windows or Mac computer or more properly among programmers, installed on a Raspberry Pi.
The most common thing done with Open CV would be to use a camera to recognize faces in a crowd or some kinds of faces.
This is where your computer will have either a Webcam plugged into your windows/mac or into your Raspberry pi and you will capture still images or videos and the program that you will access will detect and analyze the images and do something with this information.
You have probably seen on tv examples of this technology where people are being watched in a crowd scene and green or some color boxes are following the people around where they walk in the scene.
Some will call this a blantant privacy violation and others will just call it keeping an eye on things.
But this whole concept of computer vision means that you are using still or moving images and using your computer and programs to detect and analyze these images and what is inside of them and then do something with this massive, massive, massive amount of information if you are filming a crowd with a handful of video cameras.
To do this in Python on a Raspberry Pi you would plug in your Pi camera and then access the OpenCV API and type in a handful of commands to start taking pictures and going into a loop where you would analyze the pictures and draw a green box around the image.
Some strange terms you will come across may be “haar cascade” for example.
Just installing Python can be very challenging for beginners so try it the first day and then try it again a few days later and you might understand it better and have success.