This story was originally published on HackerNoon at: https://hackernoon.com/facial-recognition-comparison-with-java-and-c-using-hog-ryad3a24. HOG - Histogram of Oriented Gradients (histogram of oriented gradients) is an image descriptor format, capable of summarizing the main characteristics of an image, such as faces for example, allowing comparison with similar images. Check more stories related to futurism at: https://hackernoon.com/c/futurism. You can also check exclusive content about #computer-vision, #data-science, #deep-learning, #artificial-intelligence, #cplusplus, #java, #programming, #histogram-of-oriented-gradient, and more. This story was written by: @cleuton-sampaio. Learn more about this writer by checking @cleuton-sampaio's about page, and for more stories, please visit hackernoon.com. Facial Recognition Comparison with Java and C ++ using HOG - Histogram of Oriented Gradients (histogram of oriented gradients) This article and tutorial is from two years ago and I decided to update and modernize the source code to publish again. In this demonstration I will use the dlib library, in a C ++ program, to compare the HOG matrix of two face images, returning the degree of similarity between them. I will also use Java to "encapsulate" my C ++ function, since the JNI integration is done inprocess and has high performance.