Skip to Content
OpenCV with Python By Example
book

OpenCV with Python By Example

by Prateek Joshi
September 2015
Beginner to intermediate
296 pages
5h 57m
English
Packt Publishing
Content preview from OpenCV with Python By Example

Scale Invariant Feature Transform (SIFT)

Even though corner features are "interesting", they are not good enough to characterize the truly interesting parts. When we talk about image content analysis, we want the image signature to be invariant to things such as scale, rotation, illumination, and so on. Humans are very good at these things. Even if I show you an image of an apple upside down that's dimmed, you will still recognize it. If I show you a really enlarged version of that image, you will still recognize it. We want our image recognition systems to be able to do the same.

Let's consider the corner features. If you enlarge an image, a corner might stop being a corner as shown below.

In the second case, the detector will not pick up this ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

OpenCV 3.x with Python By Example - Second Edition

OpenCV 3.x with Python By Example - Second Edition

Gabriel Garrido Calvo, Prateek Joshi
OpenCV: Computer Vision Projects with Python

OpenCV: Computer Vision Projects with Python

Joseph Howse, Prateek Joshi, Michael Beyeler
OpenCV By Example

OpenCV By Example

Prateek Joshi, David Millán Escrivá, Vinícius G. Mendonça
OpenCV 4 with Python Blueprints - Second Edition

OpenCV 4 with Python Blueprints - Second Edition

Dr. Menua Gevorgyan, Michael Beyeler (USD), Arsen Mamikonyan, Michael Beyeler

Publisher Resources

ISBN: 9781785283932