[vorbis] frequency cutoff?

[Bostjan]

<<<<<<<<<<
----- Original Message -----
From: "Nicola Larosa" <nico at tekNico.net>
To: <vorbis at xiph.org>
Sent: Monday, March 11, 2002 12:35 PM
Subject: Re: [vorbis] frequency cutoff?

Cannot find the message in the archives, but if memory serves me well, Monty
said that Vorbis cuts at 16KHz at "-q 0" and at 18KHz at "-q 3", the
default. Then it goes to 22Khz somewhere around the 4 or 5 quality level.
>>>>>>>>>>

<p><p><p>Hi!
Below is Monty's mail. As he writes "lowpass is set in
lib/modes/psych_44.h", where you can read the following:

q - kHz
-------------
0 - 15.1
1 - 15.8
2 - 16.5
3 - 17.9
4 - 20.5
5 - 48.
6 - 999.
No lowpass filter above -q6.

Cheers,
Bostjan

<p><p><p><p><<<<<<<<<
On Wed, Feb 13, 2002 at 09:08:46AM +0100, Nicola Larosa wrote:
> >I was wondering about the lowpass filter applied at the different
> >quality levels. It seems that the 16kHz cut-off is still there at
> >quality 3.
>
> I can attest that on many samples the "-q 3" level goes up to 18 KHz, and
> at least on one sample (EncoderHell, found on AirWindows) it goes up to 22
> KHz.

The hard lowpass is set in lib/modes/psych_44.h.

-q3 goes to 17.9 and -q4 to 20.5

Monty
>>>>>>>>>

<p><p><p>--- >8 ----
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