Book Image

Mastering OpenCV 4 with Python

By : Alberto Fernández Villán
5 (1)
Book Image

Mastering OpenCV 4 with Python

5 (1)
By: Alberto Fernández Villán

Overview of this book

OpenCV is considered to be one of the best open source computer vision and machine learning software libraries. It helps developers build complete projects in relation to image processing, motion detection, or image segmentation, among many others. OpenCV for Python enables you to run computer vision algorithms smoothly in real time, combining the best of the OpenCV C++ API and the Python language. In this book, you'll get started by setting up OpenCV and delving into the key concepts of computer vision. You'll then proceed to study more advanced concepts and discover the full potential of OpenCV. The book will also introduce you to the creation of advanced applications using Python and OpenCV, enabling you to develop applications that include facial recognition, target tracking, or augmented reality. Next, you'll learn machine learning techniques and concepts, understand how to apply them in real-world examples, and also explore their benefits, including real-time data production and faster data processing. You'll also discover how to translate the functionality provided by OpenCV into optimized application code projects using Python bindings. Toward the concluding chapters, you'll explore the application of artificial intelligence and deep learning techniques using the popular Python libraries TensorFlow, and Keras. By the end of this book, you'll be able to develop advanced computer vision applications to meet your customers' demands.
Table of Contents (20 chapters)
Free Chapter
1
Section 1: Introduction to OpenCV 4 and Python
6
Section 2: Image Processing in OpenCV
12
Section 3: Machine Learning and Deep Learning in OpenCV
16
Section 4: Mobile and Web Computer Vision

k-means clustering

OpenCV provides the cv2.kmeans() function, which implements a k-means clustering algorithm, which finds centers of clusters and groups input samples around the clusters.

The objective of the k-means clustering algorithm is to partition (or cluster) n samples into K clusters where each sample will belong to the cluster with the nearest mean. The signature of the cv2.kmeans() function is as follows:

retval, bestLabels, centers=cv.kmeans(data, K, bestLabels, criteria, attempts, flags[, centers])

data represents the input data for clustering. It should be of np.float32 data type, and each feature should be placed in a single column. K specifies the number of clusters required at the end. The algorithm-termination criteria are specified with the criteria parameter, which sets the maximum number of iterations and/or the desired accuracy. When these criteria are...