Patent ID: 9552513
Date: 2017-01-24
CPC Classifications: G06K,G06T

Claim:
1. A method of automatic detection of a facial feature, comprising: a. obtaining a human image comprising a head, a neck, and a face; b. modeling the human head as an ellipse in vertical projection; c. fixing the center of rotation of the ellipse as the center of the neck; d. truncating the ellipse along the major axis representing a region of the face to an arc of ±60°; e. mapping a center of the face as the projection of a nose; f. locating boundaries of the face on the ellipse by identifying coordinates on the elliptic arc subtending ±60°; and g. computing a yaw angle of head rotation using position of the nose and the boundaries of the face; wherein the ellipse is described by the equation wherein the parametric form of ellipse is x=r cos t, y=βr sin t−αr, for tε[0, 2π], wherein, r is half of the frontal face width, α is a factor representing the extent of truncation, δ is a factor representing the distance of the pivot point from the center of the ellipse, β is the ratio of the major to the minor axes.