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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

What is a visual dictionary?

We will be using the Bag of Words model to build our object recognizer. Each image is represented as a histogram of visual words. These visual words are basically the N centroids built using all the keypoints extracted from training images. The pipeline is as shown in the image that follows:

What is a visual dictionary?

From each training image, we detect a set of keypoints and extract features for each of those keypoints. Every image will give rise to a different number of keypoints. In order to train a classifier, each image must be represented using a fixed length feature vector. This feature vector is nothing but a histogram, where each bin corresponds ...

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Publisher Resources

ISBN: 9781785283932