
The orthonormal wavelets, c, are constructed starting with the 2p-periodic
function H(v), which is the frequency response of
h(n) ¼
ffiffiffi
2
p
ð
f(x)f(2x n)dx (7:57)
If f has compact support, then h(n) has a finite number of nonzero moments. By
Eqs. 7.29 and 7.30, c also has compact support. The orthogonality of h(n)
implies that H(v) should satisfy Eq. 7.55.
The number of vanishing moments is related to the regularity, which de-
scribes the smoothness of f and c. The regularity is defined by the factorization
of H(v) as a trigonometric polynomial,
H(v) ¼
ffiffiffi
2
p
1 þ e
jv
2
M
R(v)(7:58)
which means that H(v) has M zeros at v ¼ p. By the orthogonality of f and c,
it ...