[Speex-dev] NB SubMode: 5

Jean-Marc Valin Jean-Marc.Valin at USherbrooke.ca
Mon Aug 7 16:44:06 PDT 2006

Le lundi 07 août 2006 à 14:55 +0200, Björn Thalheim a écrit :
> Hello,
> I do test runs of speex using
> 	speexenc -n [name].wav [name].spx
> The wav-files (6 different speech files) hereby are sampled at 44100Hz.

That's one of the most creative ways to destroy quality with Speex that
I've seen recently. Please refer to manual about why -n and 44.1 kHz
don't mix.

> Most interestingly, all Frames have SubModeID 5.

Normal, submodeID 5 is the default bitrate for narrowband.

> I haven't tracked the Assignment of the SubModeID through the source
> code, so I just wanted to ask, if I can assume "speexenc -n" to use
> SubModeID 5 always?

Only if you never change the bit-rate. But speexenc -n was a dumb idea
in the first place...


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