1. Introduction
Face verification is one of the core problems in computer vision and has been actively researched for over two decades [44]. In face verification, given two videos or images, the objective is to determine whether they belong to the same person. Many algorithms have been shown to work well on images that are collected in controlled settings. However, the performance of these algorithms often degrades significantly on images that have large variations in pose, illumination, expression, aging, and occlusion. Most face verification systems assume that the faces have already been detected and focus on designing matching algorithms. However, for an automatic face verification system to be effective, it needs to handle errors that are introduced by algorithms for automatic face detection, face association, and facial landmark detection algorithms.