[vorbis-dev] Spectral band replication

Stefan T. Böttner virtual.man at t-online.de
Thu Jun 14 04:31:33 PDT 2001

I have the following idea about this "spectral band replication":

Harmonic frequencies are integer multiples of the fundamental frequency. That 
means if you take all frequencies in a particular block (say up to 11 KHz for 
a medium bitrate encoding), double them and add them to the original at a 
lower volume, then this results in frequencies up to 22 KHz.

I suppose that taking anything else but harmonics will rather end up in more 
noise. And don't know if that's it what mp3pro does, because I didn't find 
any details, and they probably won't give them out.

I already tried this with music that I downsampled to 11 KHz, i.e. 
frequencies up to 5.5 KHz, and it did sound much better when adding the 
harmonics x2, x3, x4 or even more.

Stefan T. Boettner

--- >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.

More information about the Vorbis-dev mailing list