Machine learning

Machine learning algorithms are used extensively to build computer vision systems for object recognition, image classification, face detection, visual search, and so on.

OpenCV provides a module called ml, which has many machine learning algorithms bundled into it, including a Bayes classifier, k-nearest neighbors (KNN), support vector machines (SVM), decision trees, neural networks, and more.

It also has a module called Fast Approximate Nearest Neighbor Search Library (FLANN), which contains algorithms for fast nearest neighbor searches in large datasets.