5.1 file channel order

[its2loud]

How could something this important in the delivery world be this confusing and effed up? Avid! Fix your Documentation immediately and give us the option to change the 5.1 order on export. How can we trust anything you tell us when you’re own documentation from two years ago is wrong!

http://duc.avid.com/showthread.php?t=383774

[its2loud]

Originally Posted by BScout

Yup.

Just ran 3 tests. Always exports SMPTE order. Always shows FILM order.
Doesn't matter what path order is set in I/O.

FAQ is wrong

(even used Cubase to import/export 5.1 files from Pro Tools and always the same; in that way it's good news as everything stays outputting/routing correctly)

BScout. I'm curious. How are you testing/looking at the channel order once Pro Tools exports the file?

If the WAV is stamped with channel metadata then no matter what program you use, it will import in the order that program wants to see it ordered, right?

When I export a 5.1 interleaved WAV and use Quicktime to inspect it tells me the order is LRCLfeLsRs but i'm not certain if that's just the default channel order Quicktime wants to see it in. I'm assuming it's reading the channel info metadata in the file, but it could be remapping once inside Quicktime.

I'm just trying to wrap my head around this so I stop exporting and labeling the wrong channel order. I'm pissed that AVID did not alert any users to this important change in operation, thus potentially making headaches for anyone delivering interleaved multichannel files.

[BScout]

Originally Posted by its2loud

BScout. I'm curious. How are you testing/looking at the channel order once Pro Tools exports the file?

Two ways.
In QT7, "movie inspector" shows your stated channel named order but if you go to "movie properties">sound track>Audio settings, you'll see channel numbers and then assignment (also where you can change that info.)

Second way was using Sound Devices Wave Agent to split the poly (Wave Agent is indiscriminate about naming and will just output each interleaved file with channel number order) and then imported those split mono files into Pro Tools to see the order.

Both cases they were SMPTE.

[marcelkavka]

I started this thread because of trouble on IMPORTING files. In my setup Basehead spots files to multichannel tracks in ProTools and for a group of files most of the time(!) I get L-C-R-LFE-LS-RS. After batch converting them with ffmpeg it seems to work but sometimes I get C-L-LS... (the alphabetical order) in ProTools.

Steve from Basehead writes, BH never ever changes track order - it's PT. Well, that's what they always say...
What about Soundminer? Does anyone have trouble like this?

It would be interesting to read and edit that chunk. Which tool?

[Frank Kruse]

Originally Posted by marcelkavka

I started this thread because of trouble on IMPORTING files. In my setup Basehead spots files to multichannel tracks in ProTools and for a group of files most of the time(!) I get L-C-R-LFE-LS-RS. After batch converting them with ffmpeg it seems to work but sometimes I get C-L-LS... (the alphabetical order) in ProTools.

Steve from Basehead writes, BH never ever changes track order - it's PT. Well, that's what they always say...
What about Soundminer? Does anyone have trouble like this?

It would be interesting to read and edit that chunk. Which tool?

Works fine with soundminer.

[BScout]

Originally Posted by marcelkavka

It would be interesting to read and edit that chunk. Which tool?

Works fine in soundminer here

As I mentioned, you can see and adjust that chunk from QT7 under movie properties>sound track>audio settings.
It's probably in QTX too but I haven't checked.

[marcelkavka]

Thx!
QTX (pro does not exist anymore) shows Information / Format: "L R C LFE LS RS".
MediaInfo: "L C R, Back: L, R, LFE" (https://mediaarea.net/en/MediaInfo)
for the SAME file.
Drag and drop from Finder brings up L C R LS RS LFE in ProTools 2018.12.
Audacity: L C R LS RS LFE.

[BScout]

Originally Posted by marcelkavka

Thx!
QTX (pro does not exist anymore) shows Information / Format: "L R C LFE LS RS".
MediaInfo: "L C R, Back: L, R, LFE" (https://mediaarea.net/en/MediaInfo)
for the SAME file.
Drag and drop from Finder brings up L C R LS RS LFE in ProTools 2018.12.
Audacity: L C R LS RS LFE.

If you follow along with the discussion had earlier (up above) your bottom two (drag and drop and Audacity) are just reading the header file. Significant of nothing other than Pro Tools and Audacity can read the file header to lay out the file.

You can still get QT7 Pro and put it in your utilities folder to call upon when you want (it can coexist with QTX; it will probably stop working once macOS 10.15 comes out since it is not 64 bit)
https://support.apple.com/kb/DL923?locale=en_US
This is the display in QT7 when reading each channel:


This is different from what QT7 and QTX "Movie Inspector" (which are the same on both) shows in that it is referring to actual channels and the ability to modify (the drop down next to each channel.) If things are off, you can flip the assignments, save the audio file and re-bring into Pro Tools and see it follow your new order.

I do not know mediainfo. It appears it is using an Open Source demuxer so is just reading the audio streams embedded in the file -- there's no guarantee it is displaying any kind of direct channel order just that it is of a surround format and telling you what one audio stream contains. That's how most of them work (container>embedded streams audio and video)

If you want to know what each interleaved audio track is, you need something that de-interleaves and is header agnostic. Wave Agent from SoundDevices is like that (since it is meant for interleaving multiple audio channels of a field recorder without regard to any kind of channel layout)

[its2loud]

If you’re trying to detect the original channel order, the only problem with Wave Agent is it does not tell you the original lettering of channels. Ie. L C R etc. it will only show you the ordering through metering (1 2 3 etc) Therefore, if you’re trying to determine the order of channels in 5.1 ambience, it’s going to be very difficult unless you can audibly hear specific sound that you know are in those channels only.

[jesele]

A possible alternative for Mac by Scott Wilson:

https://github.com/muellmusik/De-Interleaver/releases


Jesper