NEW Guides and AmvApp BETA

WC Annihilus · Post by **WC Annihilus** » Fri Oct 19, 2007 5:29 pm

Guide wrote:Because of the license this software is released under, the encoder could not be directly included in the AMVApp

You are able to get it from here though

Scintilla · Post by **Scintilla** » Fri Oct 19, 2007 7:03 pm

What, Nero's AAC encoder isn't available as a free download anymore?

WC Annihilus · Post by **WC Annihilus** » Fri Oct 19, 2007 7:15 pm

Basically Nero adjusted their site with Nero 8 and the link now re-routes to Nero Digital. However, Google still has the original page cached, so you can get it there (link in my previous post)

Zarxrax · Post by **Zarxrax** » Fri Oct 19, 2007 7:23 pm

Hmm, ill have to work something out about that.

Tiiscool · Post by **Tiiscool** » Sat Oct 20, 2007 3:08 am

Hi,

a little nice typo: XviD is became Xvid

Ti

Kira_Douji · Post by **Kira_Douji** » Sat Oct 20, 2007 5:47 pm

Well thank you for the cached page - I have it now. I guess what I don't understand is why Nero offers it for free but apparently only Nero can offer it? Weird.

- Kira

Qyot27 · Post by **Qyot27** » Sat Oct 27, 2007 2:41 pm

Concerning the Nero AAC issue:
http://forum.doom9.org/showthread.php?t=130832

So maybe things will get straightened out, but there's no telling when.

Qyot27 · Post by **Qyot27** » Tue Oct 30, 2007 6:24 pm

Qyot27 wrote:Concerning the Nero AAC issue:
http://forum.doom9.org/showthread.php?t=130832

So maybe things will get straightened out, but there's no telling when.

It's now back up at this address:
http://www.nero.com/eng/nero-aac-codec.html

Qyot27 · Post by **Qyot27** » Sun Nov 18, 2007 7:32 pm

I think it would be advisable to explain some of the differences when encoding AAC streams. Particularly because of the fact that the High Efficiency profile (HE-AAC) isn't meant to be used with high bitrates, like videos distributed locally would aim for most of the time, and yet I'm seeing it getting used anyway. The default Low Complexity profile should be used instead for bitrates that aren't intentionally low, like the case would be for streaming (i.e. under 80 kbps, as that's about the cutoff for HE-AAC's usefulness with normal audio streams).

The reason is that, unless the encoder is wonky, HE-AAC achieves the quality it does by halving the frequency so that the low bitrate doesn't negatively affect things, and uses SBR to attempt to restore the lost frequencies. It can't perfectly replicate the lost data, though, and using LC at higher bitrates close to transparency (which are the bitrates I'm seeing used as it is) does a better job at preserving the audio quality, as it doesn't toss out the frequency information.

Videos I've downloaded that actually used HE-AAC correctly had very audible degradation of the sound quality, although it did certainly sound better than the bitrate that was used (mainly 64 kbps) would have sounded otherwise. However, there's truckloads of them which superficially report the use of HE-AAC but CoreAAC reports no transformation of the frequency, and the files really are still 44.1 or 48 kHz, which means that the High Efficiency hinting isn't there and the report is a false positive, or isn't doing anything if it is there.

Also it might help to reiterate the fact that iTunes Plus purchases can be converted without needing to be decrypted first. Even if it is redundant and completely obvious, it is worth noting (especially since the Plus versions are also higher bitrate than typical Store purchases).

Zarxrax · Post by **Zarxrax** » Mon Nov 19, 2007 3:17 pm

As far as the guide goes, aac encoding is explained through the use of my zarx264gui, which does not give you an option to use he-aac or not (its selected automatically by the encoder, and as long as you use a decent bitrate it should come out fine).

Granted, some people may be working with other tools, in which case this might be worth mentioning... but at the same time I don't really know if it's that necessary. There would have to be a new section added in which to explain this at, and there doesn't exist anything explaining what all of the options in LAME do, so I'm kind of inclined to lean towards thinking that if people are using something other than what I include in the amvapp, they should research all such options on their own.

Anyone else want to weigh in on this?