The VideoLAN Forums

Hey all,

Until a while ago there was no reason to run multiple audio tracks at the same time in VLC player. I mean who would want to hear all the different language audio's on top of each other? Though recently there has been a screen-recording software by a major GFX card producer that allows to record game video footage, audio and microphone audio in different tracks.

This is great, but playing it back in VLC is a hassle. I mean you have to switch between the tracks "System sounds" and "Microphone" to hear the selected one. Preferably you'd hear both the system sounds and microphone input at the same time, but as it stands it is impossible to select multiple tracks to listen to in VLC.

It would be great to be able to select multiple audio tracks at once. Even if just a setting it would be great to actually use these files the way they were meant to (without having to load them into a video editing software)

I understand if you still see no reason to do this, because for traditional media (video's and audio) this is not really relevant.


PS: The GFX card producer I am talking about is NVidea and their software for recording is ShadowPlay. I have left this at the bottom so mods can easily remove this information from the post if they find that it is advertising.

It would be good idea for adding lector - voice over only audio from external file.

I would like to extend Idea,
That it could be also in another mode.
I mean playback of one language on front speakers.
And second language on rear speakers.
And using two pair of phones instead of speakers.

I would like to playing back some mp3 on front, and other for rear.
That is:
I would dream about better multichannel management for unhindered stereo source playback for MultiRoom purposes.
As I have 4 pair of speakers (My room 2 pair, Kitchen 1 pair, and bathroom 1 pair.)

You can play all tracks, but that's too fringe case to handle in the GUI.

You can play all tracks, but that's too fringe case to handle in the GUI.

vlc --sout-all --sout #display

Understandable! Thanks for the command though! I can make a shortcut out of this to drag the file onto.

Here's the code for any incoming google searchers:

Create a text-file with this as content and rename it to something ending in .bat (on Windows). Then to play both tracks just drop the file containing those tracks onto it: If you have added VLC to your PATH environment variable you can just use "vlc" instead of the full path

vlc --sout-all --sout #display

It is good to know that VLC can do this. It is useful for audio description. Then there is an interesting behaviour: If I disable the audio in VLC menu, then I can add audio tracks one by one.

I mean playback of one language on front speakers.
And second language on rear speakers.

A multilingual audience could watch a film with 2 (or more) audio tracks playing at the same time and using only one multichannel sound card in computer, one audio track through front speakers and the second one through headphones (rear speakers). Probably it is possible to achieve this using "Audio channel remapper" audio filter and 2 VLC instances running in "Network synchronization" mode (netsync works if a slave is started at first and then the master aferwards). I cannot test it as I have only stereo output at the moment. Here is some old related topic with some ideas: https://forum.videolan.org/viewtopic.php?f=7&t=95501
Perhaps VLC could improve these features in the future and find a user-friendly way of implementation in the GUI.

vlc --sout-all --sout #display

It is good to know that VLC can do this. It is useful for audio description. Then there is an interesting behaviour: If I disable the audio in VLC menu, then I can add audio tracks one by one.

But then you miss a lot of features

I mean playback of one language on front speakers.
And second language on rear speakers.

A multilingual audience could watch a film with 2 (or more) audio tracks playing at the same time and using only one multichannel sound card in computer, one audio track through front speakers and the second one through headphones (rear speakers). Probably it is possible to achieve this using "Audio channel remapper" audio filter and 2 VLC instances running in "Network synchronization" mode (netsync works if a slave is started at first and then the master aferwards). I cannot test it as I have only stereo output at the moment. Here is some old related topic with some ideas: https://forum.videolan.org/viewtopic.php?f=7&t=95501
Perhaps VLC could improve these features in the future and find a user-friendly way of implementation in the GUI.

Not a priority, to be honest.

It would be great to have such feature, i'll explain my situation:
Broadcasting side: 32 channels audio, 2 video inputs (HD-SDI) . I'd like to map then to different PID's in an MPEG stream.
Receiving side(s):
Split audio to 32 channels again so it can be mixed locally (mapped to multitrack sound module or Dante) and output the video to HD-SDI again.

I'm familiar with x264, so encoding and decoding should not be a problem. But mapping to different devices is currently not possible as far as I know, and I'm concerned about keeping all audio tracks and video sync.

Between the sites there is a 'lossy' Internet-connection, so a TCP-based protocol with buffering is mandatory.

Basicly, mapping PID's to devices and vice-versa should already enable most of this case, and also is useful for the case of mederi

I have a similar task. There are lot of blu-ray movies with new Dolby ATMOS/DTS:X audiotracks (in english), but there are included only DD5.1 localized audiotracks.
I'm trying to do my own custom player via vlcLIB, witch support 2 simultaneous synchronous instance of vlclibplayer playing to 2 output devices - HDMI (for all 7.1.4 except center channel) and analog output (for center channel). This option is suitable for any modern laptop.
All works good, but I cannot force vlclib to switch audio ouput to HDMI pass-through.
I've opened the thread: https://forum.videolan.org/viewtopic.php?f=32&t=146797
Hope someone helps me.

Basicly, mapping PID's to devices and vice-versa should already enable most of this case, and also is useful for the case od of mederi

I was able to do this all with ffmpeg. A pity VLC does not implement the mapping like ffmpeg does.

VLC is seeing all the mono audio PID's well, but plays only one at a time.

VLC is seeing all the mono audio PID's well, but plays only one at a time.

Which is the correct thing to do, tbh. One track is one track. If you want 32channels, put 32channels in the same track.

If anyone else is still looking for this feature, I have filed a subsequent feature request with additional usage scenarios: https://forum.videolan.org/viewtopic.php?f=7&t=150416

@TheJokerR Thanks for the tip for creating the batch file.

This feature is also useful for gamers. I record my game session with the mic channel saved to a separate audio file. AMD's software has the ability to record like this out of the box. However I couldn't find a way to play it back with both the audio in the main video file along with my mic input without going into an edition software.

Dragging both files on the .cmd file works perfectly.

VLC is seeing all the mono audio PID's well, but plays only one at a time.

Which is the correct thing to do, tbh. One track is one track. If you want 32channels, put 32channels in the same track.

Unfortunately, the MPEG TS muxer did not allow me to. The source and target were actually 24-channel sound cards (Allen&Heath QU mixers), and I had to split it in order to be able to stream them.

You can play all tracks, but that's too fringe case to handle in the GUI.

vlc --sout-all --sout #display

Unfortunately, this method did not work on mac os (Catalina).
And when specifying a playlist in the command line, and when loading it after launch, only one stream is played.

You can play all tracks, but that's too fringe case to handle in the GUI.

vlc --sout-all --sout #display

Understandable! Thanks for the command though! I can make a shortcut out of this to drag the file onto.

Here's the code for any incoming google searchers:

Create a text-file with this as content and rename it to something ending in .bat (on Windows). Then to play both tracks just drop the file containing those tracks onto it:

Code: Select all

start "" "C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" --sout-all --sout #display %1%

If you have added VLC to your PATH environment variable you can just use "vlc" instead of the full path

I couldn't get this to work for the life of me. As it turns out, it was my VLC player version causing issues. I was trying to run this on VLC 3.0.11 whereas I had a friend test this on his VLC (version 3.0.3). It didn't work on my player but it worked on his. Needless to say, downgrading my VLC to 3.0.3 fixed the issue.

Hi!
How to attach any|extra audio track to video which has no audio?
https://cloud.mail.ru/public/FctU/KGxnsMHBN

This is like a request for the feature.

Thank you.

Greetings. Am grateful for the broad functionality and versatility of VLC. This is the first time I've posted to the Forum.
In my work, I use VLC for reviewing .TREC (Camtasia) recording files before I edit and produce them out. It happens that the .TREC format has my mic on one track, and the system audio (such as Zoom) on a separate track. I use the recommended syntax to successfully merge the audio tracks.
Question: Is there a variation on the syntax which will also enable adjustment of the playback speed? (I observe that, when using this startup command, the recording will play at 1.0x, and no other speed.)
(Am on Win10, and have updated to v3.0.12 Venitari.) Thank you in advance for any assistance you might be able to provide.

I think Professional TV Broadcast should broadcast voice over in this way:
Big Dolby DTS, Dolby Atmos, or AC-4 stream with 10Mb/s
and additional stream with just Voice Over encoded just at 64kb/s.

So much Broadcasted TV does not allow to switch to Original Language Track.
And it would be much better that modern reception equipment on client side would just mix two Language track into one



What is more this metod could be used very easy to playback 4K UHD content, like Blu Ray,
who do not have any localisation for current language,
So if someone would purchased 4K UHD Blu Ray disc without for example Arabic or Russian version,
but had such Voice Over for DVD purposes, or could used some soft to extract Voice Over from DVD,
(I suppose it is not impossible, since There is original language track on DVD, and could just to subtract Voice Over from one soundtrack using second soundtrack)
and use such small Voice Over File, with VideoLan during playback.

DVDs are avaiable for most languages,
But 4K UHD content or BluRay only for selected ones.

Why jut not allow to select several tracks using already existing UI?
It woudl be very handy.

Because it would be very tedious for the 99.999% of users who just want to change the audio track, and control the one active audio track.

Its only tedious if its the default behaviour. With opt in, everyone gets the best of both worlds (think of ctrl-clicking html <select> element with 'multiple' attribute set)

Count me as another game clipper who would like to hear their split game/mic/discord tracks together without resorting to cli args

If it's not visible by default it's completely useless as nobody will know that the feature even exists. And if it is visible by default then it will make the UI more tedious; that's what I wrote.

But if you have a non-tedious concept, you're welcome to send a patch.

You can play all tracks, but that's too fringe case to handle in the GUI.

Code: Select all

vlc --sout-all --sout #display

You have no idea how many gamers and streamers will be grateful to you if you add this setting to the graphical interface of the program.
Because when editing, or rather when viewing and selecting, a large number of recordings with two tracks, this is very much in demand.
And for gamers, when video is captured, system sounds and microphone sounds are very often written to different audio tracks.

I join the question that I quoted below.
When starting the program with settings for playing two audio tracks, the hotkeys for increasing and decreasing the playback speed do not work. Are there additional settings for changing the playback speed to work?

Greetings. Am grateful for the broad functionality and versatility of VLC. This is the first time I've posted to the Forum.
In my work, I use VLC for reviewing .TREC (Camtasia) recording files before I edit and produce them out. It happens that the .TREC format has my mic on one track, and the system audio (such as Zoom) on a separate track. I use the recommended syntax

Code: Select all

vlc --sout-all --sout #display

to successfully merge the audio tracks.
Question: Is there a variation on the syntax which will also enable adjustment of the playback speed? (I observe that, when using this startup command, the recording will play at 1.0x, and no other speed.)
(Am on Win10, and have updated to v3.0.12 Venitari.) Thank you in advance for any assistance you might be able to provide.

Rémi Denis-Courmont

To be honest, this is the only thing missing, I have even got used to the rest of the inconveniences and adapted to work with them.
Tell me if it is possible to enable accelerated playback in the playback mode of two audio tracks.
I join the question that I quoted below.
When starting the program with settings for playing two audio tracks, the hotkeys for increasing and decreasing the playback speed do not work. Are there additional settings for changing the playback speed to work?

Greetings. Am grateful for the broad functionality and versatility of VLC. This is the first time I've posted to the Forum.
In my work, I use VLC for reviewing .TREC (Camtasia) recording files before I edit and produce them out. It happens that the .TREC format has my mic on one track, and the system audio (such as Zoom) on a separate track. I use the recommended syntax

Code: Select all

vlc --sout-all --sout #display

to successfully merge the audio tracks.
Question: Is there a variation on the syntax which will also enable adjustment of the playback speed? (I observe that, when using this startup command, the recording will play at 1.0x, and no other speed.)
(Am on Win10, and have updated to v3.0.12 Venitari.) Thank you in advance for any assistance you might be able to provide.