Re: [LAU] Requirements for huge multitrack editing

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
To: <linux-audio-user@...>
Date: Tuesday, November 13, 2012 - 10:49 am

On Mon, Nov 12, 2012 at 02:39:17PM -0800, Len Ovens wrote:

> To change things to 48k you would have to do that outside of ardour. I

You must be using a *really* crap resampling app if you get that
sort of effects.

If you import the tracks in Ardour with resampling, or if you
use sndfile-resample, the work is done by Erik's libsamplerate.
This uses (double precision) floating point to maintain the
filter phase, and that will indeed lead to accumulating roundoff
errors. But in practice these are *absolutely insignificant*.

I actually did the test, checking the timing after 10 hours
of resampling from 44.1 to 48 kHz. Within the precision of
the test (around 1 millionth of a sample, 25 picoseconds)
there was *zero* error.

And if you use zresample the problem doesn't exist by design,
as it uses only rational arithmetic (i.e. all integers) to do
the same calculations.

Ciao,

--
FA

A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)

_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@lists.linuxaudio.org
http://lists.linuxaudio.org/listinfo/linux-audio-user

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[LAU] Requirements for huge multitrack editing, Asa Marco, (Mon Nov 12, 7:02 pm)
Re: [LAU] Requirements for huge multitrack editing, Len Ovens, (Mon Nov 12, 10:39 pm)
Re: [LAU] Requirements for huge multitrack editing, Fons Adriaensen, (Tue Nov 13, 10:49 am)
Re: [LAU] Requirements for huge multitrack editing, Len Ovens, (Tue Nov 13, 2:41 pm)
Re: [LAU] Requirements for huge multitrack editing, Asa Marco, (Tue Nov 13, 9:28 am)
Re: [LAU] Requirements for huge multitrack editing, Len Ovens, (Tue Nov 13, 2:37 pm)
Re: [LAU] Requirements for huge multitrack editing, Thomas Vecchione, (Tue Nov 13, 12:13 pm)
Re: [LAU] Requirements for huge multitrack editing, Asa Marco, (Tue Nov 13, 4:14 pm)
Re: [LAU] Requirements for huge multitrack editing, Paul Davis, (Mon Nov 12, 7:17 pm)
Re: [LAU] Requirements for huge multitrack editing, Jannis Achstetter, (Mon Nov 12, 9:18 pm)
Re: [LAU] Requirements for huge multitrack editing, Asa Marco, (Tue Nov 13, 9:13 am)
Re: [LAU] Requirements for huge multitrack editing, Fons Adriaensen, (Mon Nov 12, 8:19 pm)