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From: "Filip Wasilewski" <filipwasilewski@gmail.com>
Newsgroups: comp.soft-sys.matlab,comp.lang.python
Subject: Re: About alternatives to Matlab
Date: 19 Nov 2006 12:28:56 -0800
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sturlamolden wrote:
[...]
> Here is the correct explanation:
>
> The factorization of the polyphase matrix is not unique. There are
> several valid factorizations. Our implementations corresponds to
> different factorizations of the analysis and synthesis poyphase
> matrices, and both are in a sence correct, although numerically
> different.

Please correct me if I'm missing something but I'm pretty sure that
choice of polyphase matrix factorization for given wavelet filter bank
has influence only on speed and numerical stability of computation and
not on the result itself. Particularly it should be possible to
reconstruct analysis and synthesis filters from polyphase matrices
regardless of the chosen factorization and both the discrete wavelet
transform and the wavelet lifting scheme should give corresponding
results for chosen wavelet (one can be rewritten in the form of other).

cheers,
fw