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Subject: RE: Quick questions
From: BlueChip (cs_bluechip_at_webtribe.net)
Date: 2003-10-20


hmmm, wish I could remember what searches I typed in - my URL history seems
to be missing a chunk - yeah, I know that sounds fishy, but it's true !:(

anyway www.goo...

http://www.geocities.com/altbinariessoundsmusicclassical/vbr-encoding.htm#ch11
"Joint Stereo looks for signals that are identical in the left and right
channel and if it finds any they are encoded as mono"

with regard to the post on "you do not lose quality"
=== THIS IS NOT TRUE AT ALL ===
Whatever you may read from the net - I can personally assure you
otherwise. And Yes, I HAVE been put through the "blind test" procedure by
two of my friends now.
But if you need someone with a cool web site to say it:
http://www.mediatwins.com/FAQ/mp3_stereo_modes.htm
"However, for some audio, Joint Stereo MS may create a 'flanging' or
'swishing' effect. In these cases it's better to use 'Stereo mode'. This
mode creates 2 independent channels for both left and right. When stereo
mode is used, you should also use a higher bitrate (160 or 192 kbits) -
Stereo mode will allocate about half of this bitrate for each channel."

http://www.mp3machine.com/discussion/messages/780.shtml
quotes William Schelter, Nils Faerber, Alexander Leidinger, Oct 13, 2001:
"Using mid/side stereo [MS] inappropriately can result in audible
compression artifacts. Too much switching between mid/side and regular
stereo can also sound bad."
...which was given as a definition of Joint Stereo

http://www.iis.fraunhofer.de/amm/techinf/layer3/
"Joint stereo coding takes advantage of the fact that both channels of a
stereo channel pair contain far the same information. These stereophonic
irrelevancies and redundancies are exploited to reduce the total bitrate."
...whatever that means

I cannot find defitions that agree with ANYTHING I have read so far,
including my own post!!!
What is so illusive about mode?
Do LAME have an "official" support forum? That may be the place to get an
accurate answer!?

BC

>BlueChip wrote:
> > Since reading your contradictory definition of Joint Stereo I went and
> > looked it up and have found three further, each completely different,
> > definitions of the term.
>
>Yes, I started searching for detailed info after reading your post, too. Do
>you have any sources for your definition or any definition differing from
>mine? Would be interesting to read, but I did only find definitions similar
>to what I already wrote.
>
>Andreas Stemmer



Page was last modified "Jan 10 2012" The Rockbox Crew
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