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Lifting schemes information
lsinfo
lsinfo displays the following information about lifting schemes. A lifting scheme LS is a N x 3 cell array. The N-1 first rows of the array are elementary lifting steps (ELS). The last row gives the normalization of LS.
Each ELS has this format:
{type, coefficients, max_degree}
where type is 'p' (primal) or 'd' (dual), coefficients is a vector C of real numbers defining the coefficients of a Laurent polynomial P described below, and max_degree is the highest degree d of the monomials of P.
The Laurent polynomial P is of the form
P(z) = C(1)*z^d + C(2)*z^(d−1) + ... + C(m)*z^(d−m+1)
The lifting scheme LS is such that for
k = 1:N-1, LS{k,:} is an ELS, where
LS{k,1} is the lifting type 'p' (primal) or 'd' (dual).
LS{k,2} is the corresponding lifting filter.
LS{k,3} is the highest degree of the Laurent polynomial corresponding to the filter LS{k,2}.
LS{N,1} is the primal normalization (real number).
LS{N,2} is the dual normalization (real number).
LS{N,3} is not used.
Usually, the normalizations are such that LS{N,1}*LS{N,2} = 1.
For example, the lifting scheme associated with the wavelet db1 is
LS = {... 'd' [ -1] [0] 'p' [0.5000] [0] [1.4142] [0.7071] [] }