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Subject: Re: Silence detection
From: Martin Borus (martin_at_borus.de)
Date: 2004-01-05


rockbox_at_cool.haxx.se schrieb am 05.01.04 09:11:15:

> >Activate Split should work in a way that when the Split is activated, the next time
> >the start rule would apply again a split is made - using the start prerecording
>
> Somehow I don't have a good feeling with that aproach of volume
> triggered splitting. You have specified another threshold that
> virtually does the same as the stop threshold: detect the begin of
> silence. Do we really need to detect different levels of silence for
> splitting and stopping?

For me yes:
My goal is to record complete cassettes without losing anything.
The tape noise is in the -45db range, so setting the stop level at -60db
will make sure the whole tape is recorded.
Splits should be detected even when some noise is present.
so if the sound level stays below -40db for a second I would want a split
the next time the starting level is exceeded.

> As for the "split after at least n seconds" parameter - it sholdn't be
> necessary. I consider it as a attempt to fix something that should be
> fixed by setting the other trigger parameters properly. Somehow it is
> the specification of a minimal song lenth.

You could also call it minimum song length. This is a better name then
my suggestion.

> But the problem that this parameter is supposed to fix is something else: avoid to detect
> silence by error. That can occur after the minimal song length too. So
> this parameter doesn't really fix the problem.

I consider this parameter a safety net. You're right - if does not fix the problem,
but prevents that you get many small files in case you chose unfortunate levels.

Regards
Martin

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