[Mp4-tech] [Audio] Intensity Stereo and M/S stereo

[Grigory A.]

Hi, Saptarshi!
If you are interesting in mp3 answer on your question is "yes"
and I can recommend you to look how this "problem" is solved in MAD
open source mp3 decoder.
http://www.underbit.com/products/mad/
SG> Hi all,
SG> Can anyone clarify the following doubt?
SG> Can BOTH Intensity stereo and M/S stereo be required
SG> to be used on a single scalefactor band ? (it seems
SG> yes, from the specifications which describes the
SG> functions invert_intensity( ) to reverse the phase of
SG> intensity if M/S has been used for a particular sfb)
SG> If yes, then it seems that a considerable number of
SG> redundant operations will have to be done in case of a
SG> sfb where both have been used. Since in M/S, we derive
SG> the left and right channel info from what is
SG> transmitted in the stream, and then in Intensity
SG> stereo tool, we overwrite the info derived for the
SG> right channel by 
SG>      right channel data = scale * left channel data
SG> Thus the calculations done during M/S processing
SG> become redundant.
SG> Could anyone help in this regand?
SG> Regards,
SG> Saptarshi.
SG> __________________________________
SG> Do you Yahoo!?
SG> New and Improved Yahoo! Mail - Send 10MB messages!
SG> http://promotions.yahoo.com/new_mail 
SG> _______________________________________________
SG> NOTE: Please use clear subject lines for your posts. Include
SG> [audio, [video], [systems], [general] or another apppropriate
SG> identifier to indicate the type of question you have.
SG> Note: Conduct on the mailing list is subject to the Antitrust
SG> guidelines found at
SG> http://www.mpegif.org/public/documents/vault/mp-out-30042-Antitrust.php
-- 
Best wishes,
=====================================
Grigory A.
s/w engineer LetsVision Co., Ltd.
IT Venture Bldg E304
SongPaGu, GaRakDong 78
Seoul, South Korea
tel:     +82-2-2142-1267
fax:     +82-2-2142-1269
cell ph: +82-10-318-400-55
e-mail:  grigory letsvision.com