Quicktime true VBR codec, best aac / m4a codec

[TechVsLife]

I know that dbpoweramp has a command line codec to add any command line encoder, but the quicktime pro true vbr aac encoder does not have a windows command line interface (and it's not available as an option from itunes either, at least not yet). So this is a feature request. Thanks.
(It might be relatively easy to do using the quicktime sdk and a script file, if it has a COM interface--or it might not.)

These results show (using a slightly older qt) that quicktime true vbr aac might now be the best aac by a significant margin (at about the same bitrate as nero, scoring 4.7 versus 4.0). The thread also shows how clunky it is to get quicktime to produce a true vbr file--a two step process involving conversion to quicktime movie and then passthrough conversion to m4a/mp4 audio:

http://www.hydrogenaudio.org/forums/index.php?showtopic=66949

Related thread:

http://www.hydrogenaudio.org/forums/index.php?showtopic=60117

Explanation of the "two-step export" process to create the audio file (steps are almost identical in quicktime pro for windows, except note that the simple "afconvert" commandline method is not available):

http://developer.apple.com/technotes/tn2008/tn2237.html

Note also that the two-step process strips/loses the tags from the original source file, even if the source file is Apple lossless.

[DarkZod]

Re: Quicktime true VBR codec, best aac / m4a codec

I agree with you,i hope it is implemented because i think it's the best thing ever. I tried it on Mac OS X with XLD (which easlily uses Quicktime Core to make TRUE VBR) and setting encoder quality to Max,Q 127 quality is fantastic,not to mention that are really small files so yeah a Windows implementation would be amazing!

[TechVsLife]

Re: Quicktime true VBR codec, best aac / m4a codec

Update:
for quicktime aac/m4a encoding, there is now an easy command line encoder for windows: QtAacEnc.Exe

recommended mode is tvbr (true vbr).

http://tmkk.hp.infoseek.co.jp/qtaacenc/

Edit: Note that since my original post:
1. nero has released an update of its aac encoder. so not clear which encoder is better now but both certainly are very good and well tested. (a new aac listening test at hydrogenaudio.org may help decide which is better.)

2. apple also has released an update of its quicktime encoder, and the q127 setting now produces much higher bitrate files (~320kb). (i.e. the vbr range has been increased.) However, lower q settings will produce bitrate files in size equivalent to the old q127.