jhardis wrote:
On Sep 30, 5:11 pm, SFTV_troy wrote:
HE-ACC + SBR is the codec used in Hybrid Digital Radio, Digital Radio
Mondiale, and DAB+.

1) The ACC is an athletic conference within the NCAA. You mean AAC.

The "AAC girls" was Playboy's best issue.

;-)



2) There is no such thing as "Hybrid Digital" radio. HD Radio is
a trademark of iBiquity Digital Corp for their IBOC implementation,
and the "HD" doesn't mean anything in particular.

False. Go look it up on wikipedia, and you will see a link to an
email from the HD Alliance. That email confirms that HD means Hybrid
Digital.



3) "HD Radio" uses a codec known as HDC (a.k.a. "HD Codec"). While
iBiquity has acknowledged that it uses SBR, they have pointedly
declined to discuss whether or not it has any other similarity to HE-
AAC. I doubt that you could cite an authoritative source, but if you
could I would love to know about it.


(1) Wikipedia states it is AAC.

(2) Even if wiki is wrong, you find that SBR codecs are the most-
advanced. Take MP3pro for example, which is essentially MP3 + SBR.
It routinely ties with AAC+SBR in listening tests.

(3) iBiquity has already stated it is "based on MPEG4", the most-
advanced standard currently available for audio compression.

So to summarize: We know definitely that it's MPEG4 with SBR. We know
wikipedia states it is based upon AAC. It's safe to make an educated
guess that HDC == MPEG4 AAC+SBR, or a derivation thereof.