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Face Recognition. By Sunny Tang. Outline. Introduction Requirements Eigenface Fisherface Elastic bunch graph Comparison. Introduction. What is face recognition? Applications Security applications Image search engine. Requirements. Accurate Efficient Light invariant
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Face Recognition By Sunny Tang
Outline • Introduction • Requirements • Eigenface • Fisherface • Elastic bunch graph • Comparison
Introduction • What is face recognition? • Applications • Security applications • Image search engine
Requirements • Accurate • Efficient • Light invariant • Rotation invariant
Eigenface • Euclidean distance between images • Principal component analysis (PCA) For training set T1, T2, …… TM Average face ψ = 1/MΣTM Difference vector φi = Ti –ψ Covariance matrix C = 1/MΣφn φTn
Recognition • Projection in Eigenface Projection ωi = W(T – ψ) W = {eigenvectors} • Compare projections
Fisherface • Similar approach to Eigerface • Fisher’s Linear Discriminant (FLD) • PCA • Scatter Matrix • Projection Matrix
Fisherface • FLD • Between-class scatter matrix • Within-class scatter matrix • Projection Matrix
Elastic Bunch Graph • Gabor wavelet decomposition • Gabor kernels
Jets • Small patch gray values • Wavelet transform
Comparing Jets • Amplitude similarity • Phase similarity
Face Bunch Graphs (FBG) • Stack like general representation • Two types of FBG: • Normalization stage • Graph extraction stage • Graph similarity function
Graph Extraction • Step 1: find approximate face position • Step 2: refine position and size • Step 3: refine size and find aspect ratio • Step 4: local distortion
Recognition • Comparing image graph • Recognized for highest similarity
Comparison • Eigenface • Fast, easy implementation • Fisherface • Light invariant, better classification • Elastic bunch graph • Rotation, light, scale invariant