[vorbis-dev] When can we expect low bitrate encoding?

[MC Spanky]

On Fri, 8 Dec 2000, Monty wrote:

> Oggenc just doesn't know how to lowpass or downsample; if you feed it
> an input source that's lower than 44.1kHz, it will Do The Right Thing
> (tm); 11kHz inputs currently compress down to as low as 16kbit/s.
> 
> That said, the encoder modes are not yet well tuned for lower sampling
> rates; specifically, the preecho handling doesn't yet scale down so
> preecho will be slightly more annoying at 22kHz, and fairly pronounced
> at 11kHz sampling rates.  That, obviously, will be corrected in the
> not too distant future.

Hmm.  So to encode a mono stream at less than 64 kbit/s, i need to start
by reducing it to 22kHz sample rate, i.e. dropping frequencies above 11
kHz.  Is this optimal?  i.e. would a fancy pants psycho-acousical
genius, given the 44.1kHz version, start by filtering out those high
frequencies anyway?  If not, are there are plans to implement 44 kHz ->
less than 64 kbit/sec for mono streams?

Thanks,
Spanky

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.