Human faces: a review from detection to recognition

Abstract

In this paper, we review researches on human faces from aspect of face recognition and face detection. Face emotion recognition are also reviewed. The study of human faces has much assistance on computer vision and machine learning research. We can identify the age, gender, and ethnic origin from faces. Face recognition systems are divided into the holistic approach and the analytic approach. The holistic approach treats a human face as 2D pattern of intensity variation. The analytic approach recognizes a human face using the geometrical measurements taken among facial features, such as eye and mouth. The face emotions are applied in robot to helf patients, senior citizens and disable people. Some time the robots are known as welfare robot. The face emotions are recognized using features such as eye, eye brow and mouth. These features play a vital role in emotion recognition. Face detection is a crucial step for face recognition and previously reported is classified into two groups: algorithms for detecting human faces in intensity images and algorithms for detecting human faces in color images.