Eigenfaces are a set of eigenvectors used in the computer vision

Computer vision

Computer vision is a field that includes methods for acquiring, processing, analysing, and understanding images and, in general, high-dimensional data from the real world in order to produce numerical or symbolic information, e.g., in the forms of decisions...

 problem of human face recognition

Facial recognition system

A facial recognition system is a computer application for automatically identifying or verifying a person from a digital image or a video frame from a video source...

. The approach of using eigenfaces for recognition

Facial recognition system

A facial recognition system is a computer application for automatically identifying or verifying a person from a digital image or a video frame from a video source...

 was developed by Sirovich and Kirby (1987) and used by Matthew Turk and Alex Pentland

Alex Pentland

Alex Pentland is the Toshiba Professor at MIT, a serial , and is one of the most cited . Pentland obtained his Ph.D. from MIT in 1981, was Lecturer at Stanford University in both computer science and psychology, and joined the MIT faculty in 1986, where he became Academic Head of the Media...

 in face classification. It is considered the first successful example of facial recognition technology

Facial recognition system

A facial recognition system is a computer application for automatically identifying or verifying a person from a digital image or a video frame from a video source...

. These eigenvectors are derived from the covariance matrix

Covariance matrix

In probability theory and statistics, a covariance matrix is a matrix whose element in the i, j position is the covariance between the i th and j th elements of a random vector...

 of the probability distribution

Probability distribution

In probability theory, a probability mass, probability density, or probability distribution is a function that describes the probability of a random variable taking certain values....

 of the high-dimension

Dimension

In physics and mathematics, the dimension of a space or object is informally defined as the minimum number of coordinates needed to specify any point within it. Thus a line has a dimension of one because only one coordinate is needed to specify a point on it...

al vector space

Vector space

A vector space is a mathematical structure formed by a collection of vectors: objects that may be added together and multiplied by numbers, called scalars in this context. Scalars are often taken to be real numbers, but one may also consider vector spaces with scalar multiplication by complex...

 of possible faces of human beings.
A set of eigenfaces can be generated by performing a mathematical process called principal component analysis (PCA) on a large set of images depicting different human faces.