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NCTU PlusX technology

A new high freq bandwidth extension technology comes from NCTU signal processing labs, which creates missing high frequencies in the decoding phase.

NCTU has been basing so far all of their results and claims of all of their codecs on PEAQ ODG numbers (NCTU-FAAC,NCTU-LAME, NCTU-Lame-plusX), and also claim their NCTU-Lame PlusX is better than AAC. But it is interesting read nontheless, and the planned listening tests (initiated by Ivan) should be interesting.

The PlusX techonology is independent of the encoder, and they will soon introduce AAC+X.

http://psplab.csie.nctu.edu.tw/projects/in...x.pl/plusx.html
http://psplab.csie.nctu.edu.tw/invboard1_2...p?showtopic=889
http://psplab.csie.nctu.edu.tw/invboard1_2...p?showtopic=888
Juha Laaksonheimo

NCTU PlusX technology

Reply #1
No sources available...

NCTU PlusX technology

Reply #2
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No sources available...

Yes. These guys are actually blatantly violating the LGPL (FAAC and Lame) by refusing to provide the source code when it is asked.

More info:
http://www.audiocoding.com/programs.php

NCTU PlusX technology

Reply #3
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Quote
No sources available...

Yes. These guys are actually blatantly violating the LGPL (FAAC and Lame) by refusing to provide the source code when it is asked.

More info:
http://www.audiocoding.com/programs.php

Yes, well.. no can do. They say that they will release the sources when their source is more mature. This issue has been beaten to death at their forum, so I think that doesn't need to be continued.

The PlusX decoding does provide frequencies up to 22khz, and it indeed can sound better because of that, than without it, but it does not conceal mp3/aac encoding artifacts, like they claim. It seems that they want to give the impression that the only artifact type there is, is the bandwidth limitation of upper frequencies, which they are trying to fix with PlusX.. If that would be the case, we had the "CD-quality codec" 5 years ago.. VQF-96. 

Edit: They seem indeed going for the open source direction. http://sourceforge.net/projects/nctu-faac/ although there are no files there yet.
Juha Laaksonheimo

NCTU PlusX technology

Reply #4
What concerns me more - is the ODG results they are reporting - they are usually better than QT AAC, Nero AAC -  even with their MP3 encoder!!

Of course, we tested the samples done with NCTU-LAME and NCTU-FAAC and the quality was far below the AAC level for many tracks (I am trying to convince them to perform a public subjective listening tests),  making some other questions very interesting - how did they manage to get such low ODG while still producing artifacts that are noticeable.

NCTU PlusX technology

Reply #5
Hmm... PlusX
Anyone remembers PlusV?
I wonder if there is a relationship, with both dealing with SBR-like technique..

NCTU PlusX technology

Reply #6
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Yes, well.. no can do. They say that they will release the sources when their source is more mature. This issue has been beaten to death at their forum, so I think that doesn't need to be continued.

Claiming their product is too immature to release source code doesn't justify releasing illegal, copyrighted binaries. They are free to keep any changes to themselves. However, if they distribute these changes, they must release the source code too.

If you want to use the product other people's work, the very least thing to do is to satisfy the requirements under which it is made available. Anything else is stealing...

NCTU PlusX technology

Reply #7
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If you want to use the product other people's work, the very least thing to do is to satisfy the requirements under which it is made available. Anything else is stealing...

Right. But the developers behind this enhancement technology are completely impervious to logic, and use the same excuses time and time again to justify their violation of the licenses.

Maybe we should try to bring shame to them, announcing the violation on Slashdot, and reporting the case to the FSF

NCTU PlusX technology

Reply #8
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If you want to use the product other people's work, the very least thing to do is to satisfy the requirements under which it is made available. Anything else is stealing...

Right. But the developers behind this enhancement technology are completely impervious to logic, and use the same excuses time and time again to justify their violation of the licenses.

Maybe we should try to bring shame to them, announcing the violation on Slashdot, and reporting the case to the FSF 

Hmm, well this is also now off-topic for this thread.. My intention wasn't to bring the license issues of NCTU-FAAC and NCTU-Lame up again (there's been enough talk about that at the NCTU's PSPlab forum and even at HA before), rather discussion about the PlusX and quality/tech related things.
Juha Laaksonheimo

NCTU PlusX technology

Reply #9
Their web site is currently down. Could somebody post the binaries somewhere please. I only want to test NCTU-Lame PlusX.

NCTU PlusX technology

Reply #10
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Their web site is currently down. Could somebody post the binaries somewhere please. I only want to test NCTU-Lame PlusX.

Unless you can accompany any such binaries with their source code, redistributing them would be illegal.

NCTU PlusX technology

Reply #11
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Hmm... PlusX
Anyone remembers PlusV?
I wonder if there is a relationship, with both dealing with SBR-like technique..

I certainly do. Used it for a while too when putting samples of music on my website. The site is still there!

http://www.plusv.org/

NCTU PlusX technology

Reply #12
to refresh some memories...  the PlusV people are behind Nullsoft's implimentation of HE AAC...  still to be announced with support in Shoutcast3.  (which seems as if it'll never come out, or even alpha test, of which im on the list)

If I heard anything about Shoutcast3, i'll post somethin here, as usual.  Btw, I have been here lurking, just havn't posted in a while because I dont have broadband at home anymore, just at my office.    Anyways, its good to see yalls...    Hydrogenaudio, then best community on teh planet   

NCTU PlusX technology

Reply #13
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Nullsoft's implimentation of HE AAC


Are you serious? I must say that this sounds very incredible, especially after my recent talks with some people from Nullsoft.

Menno

NCTU PlusX technology

Reply #14
Then slap me silly and call me ill-informed.  Its true I havnt talked with Tom in a while.    Is there something you can share?

NCTU PlusX technology

Reply #15
I asked them about that proprietory Dolby AAC, and they told they weren't going to use that (yet?). At least that's how I understood it.

Menno

NCTU PlusX technology

Reply #16
*bump*

It's too bad that they are being retarded with the sourcecode, and that they havnt been releasing more files, etc etc.  I mean it seems like it's a very usefull peice of code in some ways, but certainly isnt all that they are claiming. 

Just weird to not see a single mention of them since this thread.

Btw, Menno, u heard the new news about Nullsoft & Winamp/Shoutcast yet? 


 

NCTU PlusX technology

Reply #18
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Btw, Menno, u heard the new news about Nullsoft & Winamp/Shoutcast yet? 

If you say what news you mean it would be easier for me to answer that question 

Menno

 
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