Frank Klemm schrieb am Don, 31 Aug 2000:
> :: b) LAME's filter is not much useful for highpass filtering
> ::
> External filters are available. For integration the f*cking "signed short
> int" format must be replaced by "float" or "double".
>
> I've heared (by listening) that the lame FIR high pass filter is not very
> well. Extern 4th order butterworth filter are working much better. They also
> can be used for Hifi highpass filtering (fu=30 Hz for records).
LAME has FIR filters? I thought it works on the polyphase filter bank
where you have 32 equidistant controlers.
Good filters would be nice to have, go for it...
> :: c) when you resample and want to lowpass, try to get rid off sfb21!
> ::
> Can you explain this?
long blocks have 22 scalefactor bands 0...21. But for sfb21 there are
no masking ratios and it will not be transmitted. So you cant color
that band, means you cannot adjust the quantizer stepsize for it.
(short blocks: 13 bands sfb12 will not be transmitted).
I meant, if you want a resulting bandwidth of x kHz, try to select
a outsamplerate where this does not interfere with sfb21 (short sfb12).
Ciao Robert
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