[CM] Resampling in SND

Bill Schottstaedt bil@ccrma.Stanford.EDU
Tue, 22 May 2007 04:31:14 -0700


> I've noticed that save-sound-as contains a field for sample rate  ... 
> I've tried putting a different sample rate in there but there was no 
> conversion. 
> What about if I want to change the bit-depth (from 16 to 24)? how 
> would I do that? 

Resampling is a destructive change, so save-sound-as
does not resample anything, but it will change sample 
representation (which ideally leaves the data intact) if
you set :data-format to something:
  
  (save-sound-as "gad.snd" :data-format mus-l24int)

If you really want save-sound-as to change the srate, see the 
documentation of before-save-as-hook.  Normally the :srate 
argument simply sets the new sound file header srate field.