ALAC multichannel in mp4 container, possible ? [Archive]

View Full Version : ALAC multichannel in mp4 container, possible ?

Kurtnoise

7th July 2005, 21:57

I try to create an Apple Lossless multichannel file in a mp4 container. But I found no way at this time. Does anyone know if it's possible or not ?

The only way seems to be in mov container with QT...It's not bad but I'd prefer accessory to have this kind of file directly in mp4 container.

I also tested to use graphedit for mov to mp4 conversion with 3ivx filters but it seems doesn't work with mov audio files.

bond

8th July 2005, 13:43

alac is not mpeg-4 compliant, so it might be better to place it in .mov

apart from that did you try remuxing the .mov to .mp4 (or better said .m4a!!!) with quicktime?

Kurtnoise

8th July 2005, 20:04

alac is not mpeg-4 compliant, so it might be better to place it in .mov
yeah, but vorbis in mp4 is possible. So, why not... :p

apart from that did you try remuxing the .mov to .mp4 (or better said .m4a!!!) with quicktime?
If you think about "Export..." option, then my file is transcode in stereo LC-AAC.

bond

8th July 2005, 20:12

yeah, but vorbis in mp4 is possible. So, why not... :p there are already five different ways of placing vorbis in .mp4 practically available, which also explains why its a bad idea to do it

If you think about "Export..." option, then my file is transcode in stereo LC-AAC. there is a passthrough option

SeeMoreDigital

8th July 2005, 23:27

Is multi-channel Apple lossless audio really possible?

I presumed it was only confined to 2 channel audio!

Cheers

Kurtnoise

9th July 2005, 05:44

there are already five different ways of placing vorbis in .mp4 practically available, which also explains why its a bad idea to do it
really ? Give me some links about that. It's just for curiosity...

there is a passthrough option
which is disabled... :(

Kurtnoise

9th July 2005, 05:46

Is multi-channel Apple lossless audio really possible?
Of course is possible...Do you want some samples ?

SeeMoreDigital

9th July 2005, 09:15

Of course is possible...Do you want some samples ?Yes please :)

Cheers

bond

9th July 2005, 10:20

really ? Give me some links about that. It's just for curiosity...vorbis-in-mp4 via mp4box' old method
vorbis-in-mp4 via mp4box' new method
vorbis-in-mp4 via a patched mp4creator
vorbis-in-ogg-in-mp4 via a patched mp4creator
i wont mention the fifth method ;)

Kurtnoise

9th July 2005, 10:41

Yes please...:)
Here is a short sample (http://kurtnoise.free.fr/Audio_Sample.mov). (right click...save as)

@Bond : :thanks: :D

SeeMoreDigital

9th July 2005, 19:02

Thanks Kurt,

I've just found the settings in QT7: -

http://img199.imageshack.us/img199/5794/qtapplelossless7vc.png

....and generated an 6Ch Apple Lossless "Speaker Test" file.... very nice. Thanks for pointing this feature out :)

Do you know whether its possible to convert 6Ch AC3 files to 6Ch Apple Lossless, if you install Apple's "MPEG-2 Playback Component"?

Cheers

Kurtnoise

9th July 2005, 19:49

Do you know whether its possible to convert 6Ch AC3 files to 6Ch Apple Lossless, if you install Apple's "MPEG-2 Playback Component"?

I don't know sorry.

btw, convert a lossy stream to a lossless stream is pretty useless.

SeeMoreDigital

9th July 2005, 20:14

I don't know sorry.

btw, convert a lossy stream to a lossless stream is pretty useless.Agreed...

I have an longer version of my 6Ch "speaker test" file in AC3 which I would like to convert to Apple Lossless... I guess I'll have to convert the AC3 stream to 6Ch WAV first.

Cheers

Kurtnoise

6th October 2005, 16:10

bond

7th October 2005, 13:08

what does this have to do with alac? :confused:

Kurtnoise

7th October 2005, 13:12

nothing I know. It's because I was too lazy to create a new thread for this. :o btw, I tested with my own compile and it doesn't work...

planet1

7th October 2005, 21:44

btw, convert a lossy stream to a lossless stream is pretty useless.

Well normally yes - but when the new target container/disc doesn't support the original audio format recompressing to a lossless format seems to be a better idea than picking the lossy option

Concerning mp4 and multichannel lossless audio - maybe waiting for ALS (http://www.nue.tu-berlin.de/forschung/projekte/lossless/mp4als.html) will be more "rewarding" than hoping for some vorbis-like mp4 "hack". :p

ALS might become the successor of MLP on a possible future HD-DVD Audio format.

For now Matroska is the ideal option - AFAIK it supports FLAC, WavPack & TTA, where WavPack is the most versatile choice e.g. Hybrid mode

http://wiki.hydrogenaudio.org/index.php?title=Lossless_comparison

Kurtnoise

8th October 2005, 07:17

I know...;) I wrote something like that for french people.

SeeMoreDigital

8th October 2005, 11:15

I pump this thread coz I've just seen that the last mpeg4ip tools included aac in mov file now : http://cvs.sourceforge.net/viewcvs.py/mpeg4ip/mpeg4ip/server/mp4creator/mp4creator.cpp?rev=1.50&view=log

So, does anybody can compile a fresh build please ?Are you thinking of building a "YAMB like" tool based around MPEG4IP?

Might me kinda interesting....

Cheers

Kurtnoise

8th October 2005, 19:54

Are you thinking of building a "YAMB like" tool based around MPEG4IP?
no...there is mp4UI for that.

SeeMoreDigital

8th October 2005, 20:05

no...there is mp4UI for that.Shame!

It might be cool to have two muxers that look the same but run different core softwares...

Cheers