Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases now! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Raspberry Pi Robotic Blueprints

You're reading from   Raspberry Pi Robotic Blueprints Utilize the powerful ingredients of Raspberry Pi to bring to life your amazing robots that can act, draw, and have fun with laser tags

Arrow left icon
Product type Paperback
Published in Oct 2015
Publisher
ISBN-13 9781784396282
Length 198 pages
Edition 1st Edition
Concepts
Arrow right icon
Toc

Table of Contents (9) Chapters Close

Preface 1. Adding Raspberry Pi to an RC Vehicle 2. Adding Raspberry Pi to a Humanoid Robot FREE CHAPTER 3. Building a Tracked Vehicle That Can Plan Its Own Path 4. Building a Robot That Can Play Laser Tag 5. A Robot That Can Draw 6. A Robot That Can Play Air Hockey 7. A Robot That Can Fly Index

Color finding with OpenCV


Now you'll want to use OpenCV and your webcam to track your puck. OpenCV makes this amazingly simple by providing some high level libraries that can help you. To start with, you'll want to create a basic file that allows you to establish a threshold and then display the pixels as white that exceeds this threshold. To accomplish this, you'll edit a file to look something similar to what is shown in the following screenshot:

Let's look specifically at the code that makes it possible to isolate the colored puck:

  • hue_img = cv.cvtColor(frame, cv.COLOR_BGR2HSV): This line creates a new image and stores it as per the values of Hue (color), Saturation, and Value (HSV) instead of the Red, Green, and Blue (RGB) pixel values of the original image. Converting to this format (HSV) focuses our processing more on the color as opposed to the amount of light hitting it.

  • threshold_img = cv.inRange(hue_img, low_range, high_range): The low_range and high_range parameters determine the...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime