Extracting Histogram of Gradients with OpenCV

Besides the feature descriptor generated by SIFT, SURF, and ORB, as in the previous post, the Histogram of Oriented Gradients (HOG) is another feature descriptor you can obtain using OpenCV. HOG is a robust feature descriptor widely used in computer vision and image processing for object detection and recognition tasks. It captures the distribution of gradient orientations in an image and provides a powerful representation invariant to changes in illumination and shadowing.

In this post, you will learn about HOG. Specifically, you will know:

• What is HOG, and how is it related to an image
• How to compute it in OpenCV

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