Record live screencast with n audio channels?

Music trends, latest album reviews...whatever!

Moderators: khz, MattKingUSA

Post Reply
nils
Established Member
Posts: 475
Joined: Wed Oct 22, 2008 9:05 pm
Has thanked: 16 times
Been thanked: 59 times
Contact:

Record live screencast with n audio channels?

Post by nils »

Hello,

I am looking to improve my recording of live screencasts with arbitrary number of audio channels, or rather stereo pairs.
It is for this project, where I also described the currently lengthy process of recording.
https://git.laborejo.org/lss/Multichann ... lume_Mixer

The resulting video will be used in a special video player, here is an example:
https://laborejo.org/multichannelplayer/

As you can see I already able to hack it together, but it should be easier.
I see multiple ways forward:

* Find a way to capture the desktop, or a window, as video with frame accurate jack transport start and stop. Then I can continue to use jack_capture. And fingers crossed that it stays in sync, but maybe with underlying jack transport there is a chance.

* Improve one of the existing screen-recording tools that support JACK to configure the number of audio channels. I am currently using SimpleScreenRecorder which is stereo (2 channels) by design and, according to the author, will never have more.

* OBS apparently has a way to capture more than stereo, but I was not able to come even close to that.

* Dive again into ffmpeg or gstreamer, both of which were really bad in the past for screen captures with JACK.

* I am using JACK at the moment, but since Pipewire is made for video routing maybe there is a way with that?

* Write a completely new tool. Outside of my skillset.

I would be happy for your suggestions and recommendations.

nils
User avatar
d.healey
Established Member
Posts: 477
Joined: Fri Sep 22, 2017 8:33 pm
Has thanked: 135 times
Been thanked: 55 times

Re: Record live screencast with n audio channels?

Post by d.healey »

I use OBS and setup additional audio devices in the settings page. Then set the different tracks in the advanced audio properties dialog.
Screenshot from 2022-09-21 20-32-35.png
Screenshot from 2022-09-21 20-32-35.png (29.65 KiB) Viewed 281 times
David Healey
YouTube - Free HISE scripting and sample library dev tutorials
Libre Wave - Freedom respecting instruments and effects.
ssj71
Established Member
Posts: 1294
Joined: Tue Sep 25, 2012 6:36 pm
Has thanked: 1 time

Re: Record live screencast with n audio channels?

Post by ssj71 »

I haven't done this for years but when I did the only way I found to keep things sync'd was to compile ffmpeg with an additional patch from male. I wrote a post about it, though I doubt the patch still applies. But it's all I got for ya. https://mountainbikesandtrombones.blogs ... video.html
_ssj71

music: https://soundcloud.com/ssj71
My plugins are Infamous! http://ssj71.github.io/infamousPlugins
I just want to get back to making music!
User avatar
artix_linux_user
Established Member
Posts: 134
Joined: Fri Sep 18, 2020 11:19 am
Has thanked: 16 times
Been thanked: 38 times

Re: Record live screencast with n audio channels?

Post by artix_linux_user »

In my new job, I have to work with multi audio channel setups and screencast streaming, so...I guess I will know the answer of this question very soon.
Broadcasting industry is so technology driven, and so fast paced - it is complicated...
I would never build out of tree and I would never install outside package manager
but I am just a stupid women...
Listen to my music
https://l330.bandcamp.com/
User avatar
bluzee
Established Member
Posts: 273
Joined: Mon Nov 30, 2020 11:43 pm
Has thanked: 12 times
Been thanked: 61 times

Re: Record live screencast with n audio channels?

Post by bluzee »

artix_linux_user wrote: Fri Sep 23, 2022 10:43 am but I am just a stupid women...
I don't think anyone cares to have remarks like this made in the forum.
User avatar
artix_linux_user
Established Member
Posts: 134
Joined: Fri Sep 18, 2020 11:19 am
Has thanked: 16 times
Been thanked: 38 times

Re: Record live screencast with n audio channels?

Post by artix_linux_user »

bluzee wrote: Fri Sep 23, 2022 4:01 pm
artix_linux_user wrote: Fri Sep 23, 2022 10:43 am but I am just a stupid women...
I don't think anyone cares to have remarks like this made in the forum.
I don't think anyone cares to have remarks like this made in the forum.
Listen to my music
https://l330.bandcamp.com/
nils
Established Member
Posts: 475
Joined: Wed Oct 22, 2008 9:05 pm
Has thanked: 16 times
Been thanked: 59 times
Contact:

Re: Record live screencast with n audio channels?

Post by nils »

I would like to stay on topic.

From the command line options Gstreamer seems to have the matching JACK parameters: n channels and jack transport.
If that really works, I don't know, I have to learn gstreamer first.
Post Reply