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Practical: Image pre-processing and feature extraction

A practical article, based on image pre-processing and feature extraction
An original image of a Daffodil flower on the left, next to a visualisation of the HOG feature extraction from the same image of the flower
This week we looked at data and features, and in particular how to extract features from image data.

This practical shows how to pre-process (by reshaping) a batch of images, then extract feature information in the form of HOG features.

All the instructions are in the attached pdf in the Downloads section below.

We would encourage you to type the code in as you follow the practical through, to get in the practice of writing your own code.

However, if you want it, the sample script containg all the code used in the practical can be downloaded from our Github repository at

Please let us know how you get on in the comments below.

This article is from the free online

Machine Learning for Image Data

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FutureLearn - Learning For Life

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