Audio: LFE and Center channels being switched

Getting started with a Blackmagic product? Ask questions here about setup and installation.
  • Author
  • Message
Offline

Faris Ruhi

  • Posts: 10
  • Joined: Thu Oct 31, 2013 8:35 pm

Audio: LFE and Center channels being switched

PostWed Mar 18, 2015 10:45 am

Hey there, I have a Decklink 4k Extreme Card and I've just begun to capture games.

I've noticed that when capturing from the PS4 (using HDMI), the LFE and Center Channel seem to be switched. Now I know I can switch the channels after capturing, but the thing is the output coming from the card is also doing the same thing, meaning when I'm playing, I can't hear the stuff that should be on the center channel at all, which means all dialogue, many sound effects etc, which is a problem. If this was one of the surround channels I probably wouldn't have any issue with it, and fix it in post.

When my PS4 is connected to an AV receiver or TV, audio is perfectly fine, I can hear all the contents of the center channel, Decklink seems to be interpreting the 5.1 audio wrong. I tried capturing in stereo as well, but that doesn't fix the problem, and I've tried both the 7.1 and 5.1 options in the ps4.

This is through both Blackmagic Media Express and Adobe Premiere Pro CS 6.

I figured that maybe this was discovered already and updated, so I tried to update my desktop video version, but the thing is doing that seems to cause problems, and just shows a black screen for the ps4, but outputs the video to the tv okay.

So currently I'm using the latest version that allows me to capture video properly, which is Desktop Video 9.9.6.

So any way to adjust or fix this somehow.

Edit: Also for the heck of it, installed the new desktop video software, captured a clip (meaning a black screen) with the audio, the audio still has the same issue, LFE and Center channels are switched, and the output through Media Express also seems to have the issue since again I can't hear any dialogue (which I know is there when I can obtain it in Premiere by switching the LFE and Center channels).
Offline

Tony Rivera

Blackmagic Design

  • Posts: 3365
  • Joined: Mon Aug 12, 2013 4:52 pm
  • Real Name: Tony Rivera

Re: Audio: LFE and Center channels being switched

PostFri Mar 20, 2015 3:24 pm

I'd suggest sending an email to your regions support office so we can take a closer look into this.
Support: http://www.blackmagicdesign.com/support
Info: http://www.blackmagicdesign.com/company

Follow us on Instagram:
@blackmagicnewsofficial
Offline

Rob Cork

  • Posts: 9
  • Joined: Tue May 19, 2015 1:26 pm

Re: Audio: LFE and Center channels being switched

PostThu Mar 24, 2016 2:36 am

I'm having this exact same issue while trying to capture video from my Xbox One. Center and LFE are swapped. I've emailed support and they just say that it must be coming out of the Xbox that way and my Denon receiver is somehow interpreting it correctly but the Intensity Pro 4k isn't. Seems fishy because if the Denon is hooked up to the Xbox directly, the audio is correct. If i connect the Denon to the HDMI-out of the Intensity Pro 4k, the channels are swapped. For now i'm using ffmpeg to remap the audio channels correctly but it's a pain in the process and the product should just work as advertised.
Offline

Erwan Robert-Thomasson

  • Posts: 57
  • Joined: Sun Mar 10, 2013 3:06 pm
  • Location: Paris, France

Re: Audio: LFE and Center channels being switched

PostThu Mar 16, 2017 11:33 pm

hi,
the problem is still here. i just got a 5.1 setup and can't use nor the sdi nor the hdmi audio embeded for 5.1 audio, center and lfe are swaped...
gonna have to get a dac...
Offline
User avatar

Xtreemtec

  • Posts: 3675
  • Joined: Wed Jan 02, 2013 11:48 am
  • Location: The Netherlands

Re: Audio: LFE and Center channels being switched

PostFri Mar 17, 2017 8:42 am

You could run it trough a decimator MD-HX. In this box you are able to swap audio channels in the hdmi or sdi..
Even can use this box to loop trough to your receiver and Go SDI Out to your decklink Card..
Daniel Wittenaar .:: Xtreemtec Media Productions ::. -= www.xtreemtec.nl =-
4K OBV Trailer, ATEM TVS HD, 1M/E 4K, 4M/E Broadcast Studio 4K, Hyperdeck Studio Mini, Ursa Broadcast 4K, 4K fiber converters with Sony Control
Offline

Erwan Robert-Thomasson

  • Posts: 57
  • Joined: Sun Mar 10, 2013 3:06 pm
  • Location: Paris, France

Re: Audio: LFE and Center channels being switched

PostFri Mar 17, 2017 8:53 am

thanks xtreemtec,
that's what i need indeed, but feel a bit pricy just to correct a bug...
Offline

KatieKate

  • Posts: 1
  • Joined: Sat Jan 19, 2019 2:06 pm
  • Real Name: Kate Ward

Re: Audio: LFE and Center channels being switched

PostSat Jan 19, 2019 2:29 pm

I'm having the same problem with a UltraStudio 4K and Media Express 3.5.7. After much searching, I found that I can use ffmpeg to create a new file with the LFE and C channels swapped (i.e. corrected).

Code: Select all
ffmpeg -i input.mov \
-filter_complex "pan=6c|c0=c0|c1=c1|c2=c3|c3=c2|c4=c4|c5=c5[out1]" \
-map 0:0 -c:v copy \
-map [out1] -c:a pcm_s24le \
output.mov

Notes:
- The input.mov and output.mov file names must be replaced by hand in the command.
- The command assumes output written by Media Express. If the file was manipulated and written anew by Final Cut X, change the -map 0:0 to -map 0:1. This is required because ME writes audio as stream 0, whereas FCX writes video as stream 0 and audio as stream 1.
- The command assumes a 5.1 input file, and will write out a properly ordered (L, R, C, LFE, Ls, Rs) file. The actual magic happens with the c2=3|c3=2 part of the --filter_complex flag.

On macOS, ffmpeg can be installed using Homebrew.
Offline
User avatar

Mike Wolf

  • Posts: 51
  • Joined: Wed Apr 03, 2013 12:56 am

Re: Audio: LFE and Center channels being switched

PostThu May 02, 2019 5:10 am

This is still an issue.

Just bought an SDI to HDMI 6G Mini Converter.

LFE and Center swapped when sending SMPTE Surround L/R/C/LFE/LS/RS.

I can route 3 to 4 and 4 to 3 in my output matrix, but that's just for monitoring/playback. Obviously need correct routing for mastering.

BMD please fix!
Mike Wolf, CSI
Online Editor | Colorist
mikewolfpost.com
310-357-7211
Offline
User avatar

Xtreemtec

  • Posts: 3675
  • Joined: Wed Jan 02, 2013 11:48 am
  • Location: The Netherlands

Re: Audio: LFE and Center channels being switched

PostThu May 02, 2019 10:36 am

Mike Wolf wrote:This is still an issue.

Just bought an SDI to HDMI 6G Mini Converter.

LFE and Center swapped when sending SMPTE Surround L/R/C/LFE/LS/RS.

I can route 3 to 4 and 4 to 3 in my output matrix, but that's just for monitoring/playback. Obviously need correct routing for mastering.

BMD please fix!

Send it in as a support ticket! Because this is a user forum.. Only if a lot of people have the same issues it is picked up from here. ;) But things this rare need a support ticket to get on the bugfix list.
Daniel Wittenaar .:: Xtreemtec Media Productions ::. -= www.xtreemtec.nl =-
4K OBV Trailer, ATEM TVS HD, 1M/E 4K, 4M/E Broadcast Studio 4K, Hyperdeck Studio Mini, Ursa Broadcast 4K, 4K fiber converters with Sony Control

Return to Getting Started

Who is online

Users browsing this forum: Andy Coulthurst and 8 guests