Why can't I select Audio 8 using WM Encoder 7.1???

Why can't I select Audio 8 using WM Encoder 7.1???

Post by bk9 » Sat, 21 Feb 2004 06:05:09


I "think" that since the Windows Media 9 codecs were installed, my
options during compression were changed from WM8, ACELP, etc... to
only ACELP, and other versions of Audio 9!? Even after attempting to
uninstall codecs, I could NOT get the option to compress using Audio 8
back.

PLEASE HELP! I do NOT have Windows Media Player 9 installed, only the
codecs. I would like to compress using Audio 8 and Video MPEG4-v3, but
like I said I can only compress using Audio 9 or ACELP.


thankyou!
-bk
 
 
 

Why can't I select Audio 8 using WM Encoder 7.1???

Post by Alessandro » Sat, 21 Feb 2004 06:14:29


WMAv9 is backward-compatible down to WMAv2 as long as you
use CBR encoding and configure it with only the sample and
bit rates supported by the previous versions. That is, if
you respect those guidelines, the decoder will not be able
to tell the difference from a WMAv9-encoded stream and any
previous version, you will only get a better encoded stream.


--

/**
* Alessandro Angeli
*
* MVP::DigitalMedia
*
* a dot angeli at biosys dot net
*/

 
 
 

Why can't I select Audio 8 using WM Encoder 7.1???

Post by Zarax - Di » Sat, 21 Feb 2004 21:15:47

In short words, this means that CBR profiles up to
160kbps and 44khz will be recognized and accepted by
older players...


versions
codecs, I
back.
and
able
any
stream.
 
 
 

Why can't I select Audio 8 using WM Encoder 7.1???

Post by Alessandro » Sat, 21 Feb 2004 22:35:53


WMAv2 also supported 128 and 160 Kbps @ 48 KHz, shouldn't that work too?





--

Alessandro Angeli

MVP::DigitalMedia

a dot angeli at biosys dot net
 
 
 

Why can't I select Audio 8 using WM Encoder 7.1???

Post by Naveen Thu » Sun, 22 Feb 2004 00:35:35

Yes, they all work on most players (including VBR). Here
are some limitations that I know of:
1) If bit rate is over 160Kbps, some old devices (or old
device implementations) due to a bug can not decode
properly. I beleive all PC/Mac players (at least 6.4 and
beyond) can handle full range.
2) If the sample rate is 48KHz, at least some PocketPC
implementations can not playback. At 44.1KHz, they should
be able to handle VBR files, AFAIK.
3) If you create MBR (multi-bit-rate) files, some servers
many not be able to handle all bit rates, some players
may not be able to play the best bit rate.
4) WMA Pro & WMA Lossless can be played in older players
through codec downloads; this option is not available to
devices.

So Zarax has made an 'intersection' of all these
constraints in coming up with his recommendation. You can
expand the set, based on your actual constraints.

Naveen

shouldn't that work too?

versions
codecs, I
back.
can
you
sample and
is, if
able
and any
stream.
 
 
 

Why can't I select Audio 8 using WM Encoder 7.1???

Post by Alessandro » Sun, 22 Feb 2004 00:45:34

Thanks for the detailed explanation.







--

Alessandro Angeli

MVP::DigitalMedia

a dot angeli at biosys dot net