Re: [LAU] Gain and clipping wav -> lame

From: Marc Lavallée <marc@email-addr-hidden>
Date: Sun Jul 28 2013 - 07:45:00 EEST

Hi Martin.

The "r128gain" software is not the same than "ebur128" that comes
with ebumeter. R128gain can be used to convert your files to mp3 in one
pass, while ebur128 analyse and report.

My understanding of EBU R128: what's important is the "integrated
loudness"; the recommended value is -23 LUFS. If you run ebur128
without --lusfs, the integrated loudness would be -4.9 - -23 = 18.1
So you would have to reduce the volume by 18.1dB.

--
Marc
Martin Cracauer <cracauer@cons.org> a écrit :
> Thanks again.  Things are looking much better now.  I embraced the
> concept of not being able to predict this.  Turns out I have old
> screwed up things that really benefitted from revisiting them and
> cleaning them up.
> 
> Marc Lavall??e wrote on Thu, Jul 25, 2013 at 04:45:48PM -0400: 
> > Martin Cracauer <cracauer@cons.org> a ??crit :
> > > Is there a way to hook up ebumeter to just an audio file or a
> > > stream not associated with real time? It seems to come in a jack
> > > package only.
> > > 
> > > Thanks again
> > > Martin
> > 
> > http://r128gain.sourceforge.net/
> 
> That works.  Comes in the Debian ebumeter package, BTW.
> 
> But how do I translate the output to a required db or ratio
> adjustment? 
> 
> I have a file in front of me that was maxed out amplitude wise by
> somebody else.  According to lame I needed --scale 0.64 to get it not
> to clip in lame (should be 3.9 db).  Which, BTW was not the value it
> first estimated that I would need.
> 
> ebur128 --lufs:
> Integrated loudness:     -4.9 LUFS
> Loudness range:           5.5 LU
> Integrated threshold:   -13.0 LUFS
> Range threshold:        -25.0 LUFS
> Range min:               -8.6 LUFS
> Range max:               -3.1 LUFS
> Momentary max:           -1.2 LUFS
> Short term max:          -2.4 LUFS
> 
> I don't see that any of the value correspond with what lame needed to
> not clip over a collection of different loudness clips.  (means: some
> clips that needed less --scale have higher numbers here and others
> have lower)
> 
> I assume the ebumeter output is more for making things sound even
> (between different pieces) and not directly a tool to max out
> anything, is that right?
> 
> Martin
_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@lists.linuxaudio.org
http://lists.linuxaudio.org/listinfo/linux-audio-user
Received on Sun Jul 28 16:15:01 2013

This archive was generated by hypermail 2.1.8 : Sun Jul 28 2013 - 16:15:02 EEST