Book Image

Hands-On Computer Vision with Julia

By : Dmitrijs Cudihins
Book Image

Hands-On Computer Vision with Julia

By: Dmitrijs Cudihins

Overview of this book

Hands-On Computer Vision with Julia is a thorough guide for developers who want to get started with building computer vision applications using Julia. Julia is well suited to image processing because it’s easy to use and lets you write easy-to-compile and efficient machine code. . This book begins by introducing you to Julia's image processing libraries such as Images.jl and ImageCore.jl. You’ll get to grips with analyzing and transforming images using JuliaImages; some of the techniques discussed include enhancing and adjusting images. As you make your way through the chapters, you’ll learn how to classify images, cluster them, and apply neural networks to solve computer vision problems. In the concluding chapters, you will explore OpenCV applications to perform real-time computer vision analysis, for example, face detection and object tracking. You will also understand Julia's interaction with Tesseract to perform optical character recognition and build an application that brings together all the techniques we introduced previously to consolidate the concepts learned. By end of the book, you will have understood how to utilize various Julia packages and a few open source libraries such as Tesseract and OpenCV to solve computer vision problems with ease.
Table of Contents (11 chapters)
9
Assessments

Images as arrays

JuliaImages are two-dimensional arrays, and every pixel can be either scalar or a one-dimensional array:

  • Grayscale images represent pixels as scalar values and they are called Gray
  • RGB is a three-dimensional array which represents each point in three different colors, such as red, green, and blue
  • PNG images with a transparent background are called RGBA

Accessing pixels

When you use a load command in Julia, it reads the image and encodes it in RGB. In the following example, we will see how Julia manages information for a single pixel:

using Images
img = load("sample-images/cats-3061372_640.jpg")
img[1:1, 1:1, :]

After Julia executes the preceding set of commands, you should expect to see the following...