Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
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
Python Machine Learning Cookbook

You're reading from   Python Machine Learning Cookbook 100 recipes that teach you how to perform various machine learning tasks in the real world

Arrow left icon
Product type Paperback
Published in Jun 2016
Publisher Packt
ISBN-13 9781786464477
Length 304 pages
Edition 1st Edition
Languages
Arrow right icon
Authors (2):
Arrow left icon
Vahid Mirjalili Vahid Mirjalili
Author Profile Icon Vahid Mirjalili
Vahid Mirjalili
Prateek Joshi Prateek Joshi
Author Profile Icon Prateek Joshi
Prateek Joshi
Arrow right icon
View More author details
Toc

Table of Contents (14) Chapters Close

Preface 1. The Realm of Supervised Learning FREE CHAPTER 2. Constructing a Classifier 3. Predictive Modeling 4. Clustering with Unsupervised Learning 5. Building Recommendation Engines 6. Analyzing Text Data 7. Speech Recognition 8. Dissecting Time Series and Sequential Data 9. Image Content Analysis 10. Biometric Face Recognition 11. Deep Neural Networks 12. Visualizing Data Index

Compressing an image using vector quantization

One of the main applications of k-means clustering is vector quantization. Simply speaking, vector quantization is the N-dimensional version of "rounding off". When we deal with 1D data, such as numbers, we use the rounding-off technique to reduce the memory needed to store that value. For example, instead of storing 23.73473572, we just store 23.73 if we want to be accurate up to the second decimal place. Or, we can just store 24 if we don't care about decimal places. It depends on our needs and the trade-off that we are willing to make.

Similarly, when we extend this concept to N-dimensional data, it becomes vector quantization. Of course there are more nuances to it! You can learn more about it at http://www.data-compression.com/vq.shtml. Vector quantization is popularly used in image compression where we store each pixel using fewer bits than the original image to achieve compression.

How to do it…

  1. The full code for this...
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
Banner background image