QAAC: discussion, questions, feature requests, etc., [originally a thread for a feature request] Options

[LigH]

QAAC is only a user interface for the original Apple QuickTime AAC and ALAC encoders.

[Anakunda]

Anu info about what;s new in CoreAudioCodec 7.9.8.1????

[sluggy]

Anu info about what;s new in CoreAudioCodec 7.9.8.1????

Id like to know also. I just checked to see if there was a quicktime update only to find the apple site says the latest is 7.7.1 where i have been using 7.7.2 for a while now??

[eahm]

http://www.hydrogenaudio.org/forums/index....showtopic=96970

[sluggy]

http://www.hydrogenaudio.org/forums/index....showtopic=96970

Thanks eahm, im still wondering why on the apple site the latest quicktime says 7.7.1 where 7.7.2 has been out for a while?

[eahm]

im still wondering why on the apple site the latest quicktime says 7.7.1 where 7.7.2 has been out for a while?

I was thinking the same yesterday, I guess 7.7.1 was the latest included with iTunes? Now you have to install it separately, no idea btw.

This post has been edited by eahm: Sep 13 2012, 17:24

[kevinsham]

I cannot encode mono files to aac using qaac now .
The output is always stereo no matter what parameters I tried.
It even output an HE-AAC v2 file if i specify -he.

I've installed iTunes 10.7.0.21.

[nu774]

I cannot encode mono files to aac using qaac now .
The output is always stereo no matter what parameters I tried.
It even output an HE-AAC v2 file if i specify -he.

Open with QuickTime Player->window menu->movie inspector.
Or, check with Mediainfo (install the latest version).
ffmpeg/libav seems to judge mono HE-AAC file generated by Apple encoder to be stereo.

[kevinsham]

Itunes says so

http://postimage.org/image/n3e3k99yl/

So does foobar

http://postimage.org/image/t7as83wgn/

Anyway, seems that the result is the same when I do "Create AAC Version" within Itunes 10.7: it is encoded as he-aac v2 in stereo

[kevinsham]

Seems that Itunes can keep it to mono if i encode as LE.
Encode as HE will make it HEv2 which is of course in stereo.

Encode as HE / LE in qaac both results in stereo.

[nu774]

Encode as HE / LE in qaac both results in stereo.

Not reproducing here. The result of qaac is the same as iTunes.

It's funny that iTunes says mono HE-AAC files created by itself as stereo HE-AAC v2.
It actually is not HE-AAC v2 and not using any SBR extensions including PS. I confirmed this looking into bitstream (using debugger).
In this case, QuickTime player and Mediainfo are correct.

[kevinsham]

Encode as HE / LE in qaac both results in stereo.

Not reproducing here. The result of qaac is the same as iTunes.

It's funny that iTunes says mono HE-AAC files created by itself as stereo HE-AAC v2.
It actually is not HE-AAC v2 and not using any SBR extensions including PS. I confirmed this looking into bitstream (using debugger).
In this case, QuickTime player and Mediainfo are correct.

Oh yeah, for the LC file, foobar says stereo and itunes / quicktime says mono. So the behaviour for qaac is consistent with itunes and any "issue" is that caused by itunes only.

I think quicktime actually always says he v2 files are mono: i tested one encoded with nero aac.

BTW, i notice that for the nero he v2 files: foobar says SBR+PS stereo
For the itunes he file (mono source), foobar says SBR stereo

This post has been edited by kevinsham: Sep 14 2012, 13:47

[lvqcl]

Your HE AAC file IS mono, the decoder just outputs upmixed stereo. This is because of parametric stereo, which is always signalled implicitly. Because of that, the decoder upmixes ALL mono files to stereo, even if there is no PS in the file.

Menno

[kevinsham]

Your HE AAC file IS mono, the decoder just outputs upmixed stereo. This is because of parametric stereo, which is always signalled implicitly. Because of that, the decoder upmixes ALL mono files to stereo, even if there is no PS in the file.

Menno

What "decoder" is that quote referring to?

If Mediainfo is correct, all the below behaviors is wrong:
Itunes encoded LC file with mono source is reported as LC stereo in foobar.
Itunes encoded HE file with mono source is reported as HE stereo in foobar.
Itunes encoded HE file with mono source is reported as HEv2 stereo in Itunes.

In all 3 cases: the software actually decodes to 2 channels, as verified by their "convert to wav" output.

I think it is problem with foobar and itunes then.

[kevinsham]

Your HE AAC file IS mono, the decoder just outputs upmixed stereo. This is because of parametric stereo, which is always signalled implicitly. Because of that, the decoder upmixes ALL mono files to stereo, even if there is no PS in the file.

Menno

What "decoder" is that quote referring to?

If Mediainfo is correct, all the below behaviors is wrong:
Itunes encoded LC file with mono source is reported as LC stereo in foobar.
Itunes encoded HE file with mono source is reported as HE stereo in foobar.
Itunes encoded HE file with mono source is reported as HEv2 stereo in Itunes.

In all 3 cases: the software actually decodes to 2 channels, as verified by their "convert to wav" output.

I think it is problem with foobar and itunes then.

The last test I am doing: Nero encoded HE(v1) with mono source:
Itunes reported as HEv2 stereo.

So seems that Itunes is just reporting any HE files as "v2" and try decoding as stereo.

Issues should be reported to iTunes and foobar than.

Thanks for all the prompt replies.
QAAC is a great tool.

[eahm]

nu774, sorry I have to ask this, is there an option to remove the "Tool" tag while converting? I have few iOS projects and I would like to use Apple/TVBR for music files but I don't want to show how I converted them.

If not, could you create a new version with a "-notool" or similar option?

Thanks.

This post has been edited by eahm: Sep 20 2012, 22:28

[nu774]

If not, could you create a new version with a "-notool" or similar option?

It's technically possible, but looks too special to be implemented as a generic option.
Can't you just remove tool tag after encoding?

In case you don't know how to do it, try mp4tags(CLI app) of mp4v2 project: mp4v2 download page
The following command line will remove tool tag from foo.m4a.

CODE

mp4tags -rE foo.m4a

Currently only a deprecated pre-built binary for Windows is out there and probably it has issues on non-ascii text handling, but it will be enough for this rather simple usage.

[eahm]

mp4tags works perfectly.

An option on your CLI would be amazing for mass encoding without it but it's perfect for now.

Thanks.

This post has been edited by eahm: Sep 21 2012, 03:04

[eahm]

CODE

[qaac] release 1.42 (refalac 0.53)
posted 3 hours ago by nu 774

MP4 container minor fix: added "isom" to compatible brands.
Also I started a new project [url="https://github.com/nu774/cafmux"]cafmux[/url] at github, which is a simple command line audio remuxer using CoreAudioToolbox.

https://sites.google.com/site/qaacpage/cabinet

Thanks for the update.

This post has been edited by eahm: Oct 8 2012, 18:44

[Anakunda]

There's new version: https://sites.google.com/site/qaacpage/cabi...rects=0&d=1

Fixed passband of --rate (sample rate converter of libsoxrate). Regression on 1.40. Default passband was not properly set, and resulted in audibly muffled sound when you do --rate=32000 or something.
Modified transition band width of --lowpass (was unnecessarily small).
Support CAF tag reading (qaac only).

[eahm]

There's new version: https://sites.google.com/site/qaacpage/cabi...rects=0&d=1

Fixed passband of --rate (sample rate converter of libsoxrate). Regression on 1.40. Default passband was not properly set, and resulted in audibly muffled sound when you do --rate=32000 or something.
Modified transition band width of --lowpass (was unnecessarily small).
Support CAF tag reading (qaac only).

Yes but please link to the cabinet's url (https://sites.google.com/site/qaacpage/cabinet), people know what to download by their selves.

This post has been edited by eahm: Oct 17 2012, 09:04

[eahm]

Thanks for the 1.44 update and fixiTunSMPB. One question, why qtaacenc never needs updates?

[nu774]

Thanks for the 1.44 update and fixiTunSMPB. One question, why qtaacenc never needs updates?

Well, is that kind of a question I can answer? I don't know.
I'm sorry for long standing iTunSMPB problem, I didn't notice it until now since I'm a fb2k user, and nobody reported of it.

[eahm]

Don't qaac and qtaacenc use the same "engine"? Sorry I'm not a programmer.

This post has been edited by eahm: Oct 19 2012, 16:58

[nu774]

Don't qaac and qtaacenc use the same "engine"? Sorry I'm not a programmer.

Yes, eventually same AAC encoder of Apple is used, but that's all.
These two are completely different programs written by different authors. For example, qaac doesn't use QuickTime at all.