quickie: aac and aac+ same thing?

afabco · Guru Joined: 24 Feb 2004 Posts: 380

Thrashing around with media-players.

Quick question: is aac and aac+ the same thing?
_________________
Anyone who puts a small gloss on a fundamental technology, calls it proprietary, and then tries to keep others from building on it, is a thief.
-Tim O'Reilly

yabbadabbadont · Posted: Tue Jan 16, 2007 3:50 am Post subject:

http://en.wikipedia.org/wiki/AAC%2B

I briefly looked through that but I'm still not sure if it answers your question. :lol:

Hopefully it will.

_________________

afabco · Guru Joined: 24 Feb 2004 Posts: 380

Ok, took a look at the link (thanks!), and I think the answer is "no, they aren't the same thing". Altho there are some words that lead one to think that there is backwards compatibility, that is, AAC stuff should run on AAC+ devices. But who knows?
_________________
Anyone who puts a small gloss on a fundamental technology, calls it proprietary, and then tries to keep others from building on it, is a thief.
-Tim O'Reilly

Gusar · Posted: Tue Jan 16, 2007 11:07 pm Post subject:

AAC is actually LC-AAC (low complexity), while AAC+ is HE-AAC (high efficiency). The latter is also called AAC SBR (spectral band replication).

The way HE-AAC works is that higher frequencies are stripped, but some info is stored on how these frequencies can be replicated at playback. A LC-AAC decoder will be able to decode a HE-AAC file, but it won't do the replication of the higher frequencies and because of that it will sound like crap.