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Dimensionality reduction
The set of faces is a “subspace” of the set of images.
–We can find
the best subspace using PCA
–Suppose it is
K dimensional
–This is like
fitting a “hyper-plane” to the set
of faces
•spanned by
vectors v1, v2, ..., vK
•any face x » a1v1 +
a2v2 +
, ..., + aKvK