This is the visualization of a learned HOG (Histogram of oriented gradients) detector, a trained face detector based on the small faces dataset in the examples-faces directory of Dlib. It was created with the Dlib example program fhog_object_detector_ex.cpp.
<a href="//commons.wikimedia.org/wiki/User:MTheiler" title="User:MTheiler">MTheiler</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>