[vorbis] Realtime resampling/encoding with oggenc

[David Mitchell]

> 
> As for having to kill sox... I don't have much experience with sox, but
> from what I can tell, there is no way to exit gracefully.  Man page, web
> search, deja.com search yield nothing in the way of stoping sox
> gracefully.  The best way to do it seems to be as stated.
> 
> --james

You could try putting dd in there to get the proper number of
samples. some thing like:
dd if=/dev/dsp bs=1024 count=1240312 | sox -etc -s - | oggenc

Fill in the proper options to sox and oggenc.  dd will output of
STDOUT of you don't specify an output file. I'm guessing that "-s
-" will tell sox to read from STDIN.

This will have dd read in about 2 hours worth of samples then
exit. When it does, it will send an EOF to sox, which should make
it close down, which will send an EOF to oggenc. I haven't tried
this, but it should work.

-David Mitchell

> 
> > On Tue, 15 May 2001, vorbis wrote:
> >
> > > Don't know if anybody is still missing the lame oggenc features for
> > > resampling, lowpass/highpass filters etc, but I wrote a little script that
> > > uses sox to do all the stuff I need to real-time encode oggenc from the
> > > radio, or any input device.
> > >
> > > #!/bin/bash
> > > DATE=`date '+%m-%d-%Y-(%H.%M)'`
> > > DESTIN=/video/music/perftoday
> > > export DATE=$DATE'-PerformanceToday.ogg'
> > >
> > > sox -V -r 44100 -c 2 -t ossdsp -w -s /dev/dsp -t wav - filter \
> > > 0-16000 2>/dev/null | oggenc - -o $DESTIN/$DATE -b 128&
> > > sleep 7200
> > > kill -9 $!
> > >
> > > What you see here on the first two lines should be only one.  Note the
> > > "\".
> > >
> > > As you can guess, I use this to record my favorite classical music program
> > > on NPR.  Anyway, I hope this solves somebody's problem similar to mine.
> > >
> > Is it always healthy to lowpass a signal from the radio at 16KHz?  Is it
> > the same for AM and FM?  I record most of my Ogg files from the radio
> > (usually through an intermediate tapa cassete - how does this effect?).
> > I usually encode without filtering.  I only once noticed that for a
> > particular station which was recieved very weakly, there was a parasitic
> > 18Khz noise.  Should I get into the habit of filtering?
> >
> > Unrelated question: the above script seems to kill the encoding as the
> > normal means for ending a recording - is this a safe thing?  Does it only
> > produce a little bad page/packet at the end that one can live with?
> >
> >
> 
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