Surround channel order for LPCM audio broken?

[potscrubber]

Hello - I've joined the forum in order to try and assist with this issue. (URL tags removed as they don't seem to be working).

Surround channel mapping for LPCM audio in MOV containers seems to be broken.

Please find the following file, which is a zipped MOV with 5.1 surround 16 bit LPCM audio, with SMPTE channel order of L-R-C-LFE-Ls-Rs. This file plays correctly in MCP-HC, Quicktime for Win, Vegas and others. In VLC 3.0.7 the output channel order is not correct.
http://bit.ly/2F2ELZQ
* Note, ignore the final spoken comment which describes it as AAC - see below for file sources by way of explanation. The MOV has LPCM audio.

The incorrect channel order is output like this:

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FILE SPEAKER L (1) -> L (1) R (2) -> R (2) C (3) -> Ls (5) LFE (4) -> Rs (6) Ls (5) -> C (3) Rs (6) -> LFE (4)

The same VLC player plays the MP4 AAC version correctly with correct channel mapping (link below).

All file sources are from the Fraunhofer Multichannel Audio Playback Tests page here:
https://www2.iis.fraunhofer.de/AAC/multichannel.html


The MOV LPCM 5.1 test file I provided is a remux of the 16 bit WAV version here:
https://www2.iis.fraunhofer.de/AAC/ChID-BLITS-EBU-Narration441-16b.wav
with the HE-AAC Channel ID - With H.264 Video here:
https://www2.iis.fraunhofer.de/AAC/ChID-BLITS-EBU.mp4

ffmpeg remux command line FYI:

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ffmpeg -probesize 50M -analyzeduration 100M -i "ChID-BLITS-EBU.mp4" -i "ChID-BLITS-EBU-Narration441-16b.wav" -map 0:0 -map 1:0 -c:a pcm_s16le -async 1 -c:v copy -aspect 800:600 -pix_fmt yuv420p -threads 8 -metadata creation_time=now -sn -y "ChID-BLITS-EBU_LPCM_5.1.mov"

As noted above, the MP4 AAC video plays out correctly with regard to channel order.

Please let me know if I can clarify anything.
Thanks,
pot.


MOV LPCM 5.1 MediaInfo (just container and audio due to post character limit):

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General Complete name : E:\ChID-BLITS-EBU_LPCM_5.1.mov Format : MPEG-4 Format profile : QuickTime Codec ID : qt 0000.02 (qt ) File size : 23.6 MiB Duration : 46 s 625 ms Overall bit rate : 4 253 kb/s Encoded date : UTC 2019-06-11 09:34:02 Tagged date : UTC 2019-06-11 09:34:02 Writing application : Lavf58.12.100 Audio ID : 2 Format : PCM Format settings : Little / Signed Codec ID : sowt Duration : 46 s 527 ms Bit rate mode : Constant Bit rate : 4 234 kb/s Channel(s) : 6 channels Channel layout : L R C LFE Ls Rs Sampling rate : 44.1 kHz Bit depth : 16 bits Stream size : 23.5 MiB (99%) Language : English Default : Yes Alternate group : 1 Encoded date : UTC 2019-06-11 09:34:02 Tagged date : UTC 2019-06-11 09:34:02

[potscrubber]

Updated my OP with additional information (nature of the incorrect channel order).

[Lotesdelere]

You should create a new ticket on the [url=https://trac.videolan.org/vlc/]VLC Trac[/url] with the links to your file and to this thread.

[potscrubber]

Thanks for the pointer. Have done so here. [url]https://trac.videolan.org/vlc/ticket/22420[/url]
Strangely I can no longer edit my OP.

[InTheWings]

This is fixed on master

[AlvaroB]

I have just tried. I'm in version 3.0.8 and I have this exact issue. The audio from my MKV with ProRes video and PCM 5.1 audio gets reordered and the center channel goes to the rear left one.

Other programs like MPC-HC play the audio correctly.