Re: [LAU] Dithering...should we dither about it?

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
To: <linux-audio-user@...>
Date: Sunday, March 2, 2014 - 8:56 am

On 03/02/2014 04:38 AM, Harry van Haaren wrote:

24bit integer is equivalent to 32bit float in terms of resolution, and
pretty much identical as long as the float samples are clamped between
-1.0f and 1.0f.

> I should correct my previous statement though: I *thought* I exported

actually, you *must* dither at every truncation step - if you don't, you
will lose information _and_ introduce signal-dependent requantisation
noise, which can never be removed again.
so the best approach is to only reduce the wordlength once, at the very
end of the chain, before going to CD.

some mastering people (bob katz among them) even go as far as demanding
dither at every level control in the chain.

however, if you are exporting from JACK's native 32bit float to 24bit
int _and_ you make sure that there is no sample larger than full-scale
(floats are funny :), then there is no actual loss of information, and
no dithering is required. all you do is map the 23 mantissa bits and the
sign bit of the float to the 24 bits of the integer.

--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT

http://stackingdwarves.net

_______________________________________________
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] Dithering...should we dither about it?, Brent Busby, (Sat Mar 1, 6:43 pm)
Re: [LAU] Dithering...should we dither about it?, Harry van Haaren, (Sat Mar 1, 6:51 pm)
Re: [LAU] Dithering...should we dither about it?, Harry van Haaren, (Sun Mar 2, 3:38 am)
Re: [LAU] Dithering...should we dither about it?, Philipp , (Sun Mar 2, 12:34 pm)
Re: [LAU] Dithering...should we dither about it?, Thorsten Wilms, (Sun Mar 2, 9:54 am)
Re: [LAU] Dithering...should we dither about it?, Jörn Nettingsmeier, (Sun Mar 2, 8:56 am)
Re: [LAU] Dithering...should we dither about it?, Fons Adriaensen, (Sun Mar 2, 1:59 pm)
Re: [LAU] Dithering...should we dither about it?, Harry van Haaren, (Mon Mar 3, 10:04 am)
Re: [LAU] Dithering...should we dither about it?, Paul Davis, (Sun Mar 2, 4:19 am)
Re: [LAU] Dithering...should we dither about it?, Ralf Mardorf, (Sun Mar 2, 3:47 am)