05715325 is referenced by 263 patents and cites 4 patents.

A detection system identifies a person by rapidly analyzing an image frame from a video camera for the presence of a face by reducing the image in resolution and normalizing the image to compensate for lighting changes and compares the normalized image with a background image to produce a binary interest mask. The most likely position of a face is then determined by identifying a top, bottom and sides of a possible head region to define a bounding box, normalizing the pixel data within the bounding box to further compensate for lighting variations, and resizing the box to match identification templates stored in memory. The best match from the identification templates is provided with a score indicative of the degree of the match. If the score does not exceed a first score threshold, then no face is assumed present. If the score exceeds a first and second score threshold, then a face is assumed present. If the first score threshold is exceeded but the second is not, a further eye location procedure is performed on the data to determine if a face is present.

Title
Apparatus and method for detecting a face in a video image
Application Number
8/521175
Publication Number
5715325
Application Date
August 30, 1995
Publication Date
February 3, 1998
Inventor
Keith M Andress
Plainsboro
NJ, US
Stuart C Schwartz
Princeton
NJ, US
Ming Fang
Cranbury
NJ, US
Richard D Bang
Princeton
NJ, US
Agent
Donald B Paschburg
Assignee
The Trustees of Princeton University
NJ, US
Siemens Corporate Research
NJ, US
IPC
G06K 9/00
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