Normalization Techniques for Hand printed Numerals
Family of pattern standardization
techniques based on geometrical projection is applied to a file of
digitized hand printed numerals obtained from sales clerks. The
principle involves transforming a quadrilateral specified in terms
of the convex hull of each pattern into a square. The amount of
overlap within each class of characters versus the amount between classes
is used to evaluate the degree of normalization achieved with respect to other 
published methods including size and shear normalization through moments.
CACM August, 1970
Nagy, G.
Tuong, N.
