surround channels being in different order?

[tremault]

I have an issue with my 5.1 audio being shifted to the right when downmixing to prologic 2 in handbrake.
I read on wikipedia that different file types have the channels in different orders. my file has left, right, centre, LFE, Left surround, Right surround. But each program I've tried is trying to read it as L, C, R, etc. I've found it to be impossible to change this and many google searches have come up with very little useful information.
I'm a little perplexed as to why programs don't have the option to specify your channel order. I don't really know how my file got like this or how to change it. maybe i used a wrong audio format somewhere. I'm not really looking for specific advice pertaining to my individual situation, I'm just curious to know if anyone else has had anything like this?

 

[unfair]

I've never heard of them being in another order, I thought that was a standardized thing, but I only use mkv and mp4. If you do need to remap them in a different order you can do that with ffmpeg, without losing any quality. I just googled it for a example and this comprehensive document came up that will help you do whatever you need to: https://trac.ffmpeg.org/wiki/AudioChannelManipulation

 

[daedal]

my file has left, right, centre, LFE, Left surround, Right surround. But each program I've tried is trying to read it as L, C, R, etc. I've found it to be impossible to change this and many google searches have come up with very little useful information.

I had the same problem with an MKV I ripped from a standard blu-ray after I imported it into Premiere.

I'm a little perplexed as to why programs don't have the option to specify your channel order. I don't really know how my file got like this or how to change it. maybe i used a wrong audio format somewhere. I'm not really looking for specific advice pertaining to my individual situation, I'm just curious to know if anyone else has had anything like this?

Premiere has the option to re-route the channels but it did not do it well. after re-routing, the channels were not playing in the wrong speakers anymore, but they suffered a loss in gain. I could not find a way to fix that but someone gave me the exact line of code for ffmpeg Unfair suggested.
Like you, I don't know what I did wrong in the first place.

@unfair when you convert your MKV to mp4 do you also convert DTS to AAC? I use this line:
ffmpeg -i Original_Video.mkv -c:v copy -c:a aac New_Video.mp4
I suspect the problem originates from there, but I'm not sure.

 

[unfair]

@unfair when you convert your MKV to mp4 do you also convert DTS to AAC? I use this line:
ffmpeg -i Original_Video.mkv -c:v copy -c:a aac New_Video.mp4
I suspect the problem originates from there, but I'm not sure.

Yeah I do, since Premiere doesn't play nice with DTS. I just do a copy on the video and convert the audio codec to AAC using high bitrate, not sure what bitrate it uses when you don't specify it. You might be able to use PCM instead of AAC too, I've wanted to test that for a while but just haven't had the time to play around with it yet.

 

[Dwight Fry]

What I do is separating the 5.1 channels into six mono .wav files using Audacity, and using those for editing. Upon exporting I do the opposite: export the six .wav files separately and then I create the 5.1 in Audacity again, to be muxed with the video file. If you desire a 2.0 final mix, the same can be done, only you have the center and surround channels be on both the left and right stereo channels.

 

[The Scribbling Man]

^^ you would want to ditch the LFE track as well. Alternatively, if you export in surround, there is a tool in MeGUI that will downmix to stereo for you properly.

 

[Dwight Fry]

^^ you would want to ditch the LFE track as well. Alternatively, if you export in surround, there is a tool in MeGUI that will downmix to stereo for you properly.

I don't ditch it, I just have it on both the left and right channels. Though I haven't done this that much, if I have a 5.1 source I keep it, so I don't know to what extent it is better to keep or to ditch.

 

[The Scribbling Man]

The LFE track is just low frequencies designed for a sub woofer. Keeping it in your stereo mix is at best superfluous and at worst muddies the audio.

 

[Dwight Fry]

^^ The more you know. Thank you!

 

[tremault]

Thanks for sharing your methods. This is really weird because I've tried a number of different things, splitting the channels into mono tracks and recombining them, I've tried downmixing to 2 channel surround in both Handbrake and headac3he and both times, the music seems to be pushed to the right instead of where it should me. This is so bizarre because it sounds normal in 5.1 and looking at the file in audacity seems to show L&R correctly, with the centre in channel 3, and everything else fine.
even weirder was when i separated them out, swapped the right and centre files and recombined, then when I opened in audacity it was all in a completely different order.

edit, my audio is 5.1 filmic. I don't know why it's 'filmic' to be honest, but when I pulled the DTS into resolve on a new timeline, it would only sound right when i set it to 5.1F. I'm editing in stereo though, as I have other audio sources and need to mix them properly.