Face Recognition
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•Faceisperhapsthemostcommonandfamiliarbiometricfeature.
•Thebroaduseofdigitalcamerasandsmartphonesmadefacial
imageseasytoproduceeveryday.
•Theseimagescanbeeasilydistributedandexchangedbyrapidly
establishedsocialnetworkssuchasFacebookandTwitter.
Face images
Main Steps in Face Recognition Systems
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Automatedfacerecognitionincludesthreekeysteps:
(1)Facedetection
(2)Extractionoffeatures
(3)Classification
Main Steps in Face Recognition Systems
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1)Facedetection
Itisthefirststepintheautomatedfacerecognitionsystem.Itusually
determineswhetherornotanimageincludesaface(s).Ifitdoes,its
functionistotraceoneorseveralfacelocationsinthepicture.
2)Featureextraction
Thisstepconsistsofextractingfromthedetectedfaceafeaturevector
namedthesignature,whichmustbeenoughtorepresentaface.
3)Classification
•Canbeeitherverificationoridentification.
•Verificationrequiresmatchingonefacetoanothertoauthorizeaccessto
arequestedidentity.
•Identificationcomparesafacetoseveralotherfacesthataregivenwith
severalpossibilitiestofindtheface’sidentity.