Welcome to the MacNN Forums.

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

You are here: MacNN Forums > Community > MacNN Lounge > High Efficiency AAC

High Efficiency AAC
Thread Tools
qnxde
Grizzled Veteran
Join Date: Jul 2001
Location: Sydney, Australia
Status: Offline
Reply With Quote
Sep 18, 2003, 03:16 AM
 
I don't know if Apple is thinking about implementing HE-AAC in QuickTime anytime soon, but I've decided to make up a sample for you to all hear. You may not like the peppy choice of music, but here it is.

http://www.danamania.com/~drm/fire.m4a

I don't think the MIME type is set correctly so if you want to click on that link in a browser you might want to remove the filename and rightclick/save as.

This file had a bitrate of about 32kbps. I have upsampled it to 128kbps AAC so that everyone can play it (or you would need to decode it using a command line decoder, faad)

Not bad eh? considering you could stream it over a 33.6k modem connection.
( Last edited by qnxde; Sep 18, 2003 at 05:52 AM. )

You can't eat all those hamburgers, you hear me you ridiculous man?
     
qnxde  (op)
Grizzled Veteran
Join Date: Jul 2001
Location: Sydney, Australia
Status: Offline
Reply With Quote
Sep 18, 2003, 07:32 PM
 
Wow, nobody at all is interested, thought this would have garnered more attention!

You can't eat all those hamburgers, you hear me you ridiculous man?
     
voodoo
Posting Junkie
Join Date: Mar 2001
Location: Salamanca, España
Status: Offline
Reply With Quote
Sep 18, 2003, 07:35 PM
 
it's just that everybody (here at my home) have gone to sleep so I can't play any music right now.

:shhh:
I could take Sean Connery in a fight... I could definitely take him.
     
Dex13
Mac Elite
Join Date: Dec 2002
Location: Bay Area of San Jose
Status: Offline
Reply With Quote
Sep 18, 2003, 07:59 PM
 
Originally posted by qnxde:
Wow, nobody at all is interested, thought this would have garnered more attention!
I'm Averaging 5k ...

     
Stradlater
Professional Poster
Join Date: Oct 2002
Location: Off the Tobakoff
Status: Offline
Reply With Quote
Sep 18, 2003, 08:00 PM
 
What do you mean high-efficiency? The slower encoding? Still "low-complexity", right?
     
ZackS
Banned
Join Date: Nov 2002
Location: Hell
Status: Offline
Reply With Quote
Sep 18, 2003, 08:34 PM
 
No one is interested because your host for that file is slower than death.

High speed link: http://pages.cthome.net/zacks/fire.m4a

And, yeah, that sounds amazing for 32kbps but it all depends on the kHz and number of channels. For 22kHz mono, that's not much better than Apple's AAC encoder is now.
     
Apple Pro Underwear
Addicted to MacNN
Join Date: Sep 2001
Location: NYC*Crooklyn
Status: Offline
Reply With Quote
Sep 18, 2003, 09:20 PM
 
geez, normal itunes AAC is good. why go through all this trouble?

i love music too but you guys need to relax and get a girlfriend.....or a boyrfriend.
     
qnxde  (op)
Grizzled Veteran
Join Date: Jul 2001
Location: Sydney, Australia
Status: Offline
Reply With Quote
Sep 18, 2003, 09:24 PM
 
Originally posted by ZackS:
No one is interested because your host for that file is slower than death.

High speed link: http://pages.cthome.net/zacks/fire.m4a

And, yeah, that sounds amazing for 32kbps but it all depends on the kHz and number of channels. For 22kHz mono, that's not much better than Apple's AAC encoder is now.

Sorry about the speed, it's only on a 64kbps uplink

That 32kbps file was actually 44khz stereo, if you do a spectrum analysis of it you'll see that there is a significant high frequency presence that is not there in a 22khz or probably even a 32khz recording.

Thanks for the high speed link BTW, I would have hosted it on my idisk but idisk is pretty broken in this build of 10.3 so I haven't been able to use it.

You can't eat all those hamburgers, you hear me you ridiculous man?
     
qnxde  (op)
Grizzled Veteran
Join Date: Jul 2001
Location: Sydney, Australia
Status: Offline
Reply With Quote
Sep 18, 2003, 09:26 PM
 
Originally posted by Apple Pro Underwear:
geez, normal itunes AAC is good. why go through all this trouble?

i love music too but you guys need to relax and get a girlfriend.....or a boyrfriend.
This isn't designed for encoding music into your itunes library, it's more designed for internet streaming etc, or anything where you need decent sounding audio over a low bandwidth application - for example XM Radio uses HE AAC, probably at around 64kbps or so.

P.S: I have a boyfriend

You can't eat all those hamburgers, you hear me you ridiculous man?
     
benb
Registered User
Join Date: Nov 2002
Location: Far from the internet.
Status: Offline
Reply With Quote
Sep 18, 2003, 10:21 PM
 
The quality is incredible, but I feel dirty for listening to that.

If people listen to this crap, I don't blame them for not paying for it.
     
qnxde  (op)
Grizzled Veteran
Join Date: Jul 2001
Location: Sydney, Australia
Status: Offline
Reply With Quote
Sep 19, 2003, 01:30 AM
 
Originally posted by benb:
The quality is incredible, but I feel dirty for listening to that.

If people listen to this crap, I don't blame them for not paying for it.
It's not great for acoustic at those bitrates because it works by recreating the high frequency audio on the fly, using what it has as a starting point - dance music et al is great because it has a fairly predictable and easy high end, same with pop.

Acoustic is generally a lot cleaner and so it's mistakes are much more blatant. But acoustic is a lot harder on any compression scheme and 32kbps is a damn low bitrate to expect anything at all to sound listenable.

You can't eat all those hamburgers, you hear me you ridiculous man?
     
- - e r i k - -
Posting Junkie
Join Date: May 2001
Location: Brisbane, Australia
Status: Offline
Reply With Quote
Sep 19, 2003, 03:07 AM
 
Amazing quality! How big was the original file?

[ fb ] [ flickr ] [] [scl] [ last ] [ plaxo ]
     
   
Thread Tools
 
Forum Links
Forum Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Top
Privacy Policy
All times are GMT -4. The time now is 06:51 PM.
All contents of these forums © 1995-2017 MacNN. All rights reserved.
Branding + Design: www.gesamtbild.com
vBulletin v.3.8.8 © 2000-2017, Jelsoft Enterprises Ltd.,