[Flac] flac -- exhaustive model search vs. -A <*>?
martin.leese at stanfordalumni.org
Thu Jun 14 14:28:14 PDT 2012
"Linda A. Walsh" <flac at tlinx.org> wrote:
> what does the exhaustive model search do?
I am not an expert on the guts of FLAC, but
there is some information about this at:
and scroll down to "MODELING".
> Does it try all of the functions listed under "-A" to find the 'best',
> i.e. bartlett, bartlett_hann, blackman, blackman_har-
> ris_4term_92db, connes, flattop, gauss(STDDEV), hamming, hann,
> kaiser_bessel, nuttall, rectangle, triangle, tukey(P), welch.
> Or is that something else?
That is something else.
> I've been using the -e option for a while in my flac encoding,
> but for something that sounds like it should be slow I wonder
> if it is testing all the models or if it might not be
> working correctly?
it states, "If the max LPC order is high this
can significantly increase the encode time."
This suggest that if the max LPC order is low
then using -e will not be slow.
The max LPC order is set explicitly using the
-l option or, more usually, by setting a
compression level. Compression levels are
Note that compression levels 7 and 8 also set
the -e option.
I have not attempted to explain what the LPC
order actually is because I do not understand
it well enough
Martin J Leese
E-mail: martin.leese stanfordalumni.org
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