What software and plugins use the ALSA Loopback device (Moode >= 7.1)

[adrii]

Hi

I was wondering which software or plugins on Moode (>= 7.1) use (or might use) the ALSA loopback device, and which Loopback subdevice they use, and whether they include options for selecting a different subdevice.

My reason for asking is that I share a program (mpd_oled) that includes an audio visualiser (spectrum analyser) and to do this it needs a duplicate copy of the currently playing audio. I have previously been providing a patch for Moode to enable MPD to make the copy, but I will no longer be providing this patch, and will only be providing an ALSA method, which will require configuring and using the ALSA Loopback device.

I do not want the configuration instructions and script I provide to interfere with any other applications using the Loopback device, or for their configurations to interfere with mpd_oled, and so I am trying to find out if this is likely to be an issue and how it might be avoided.

Adrian.

[Tim Curtis]

I think the CamillaDSP component might use alsa loopback. If it does try looking in the alsa_cdsp module.
https://github.com/moode-player/moode/tr.../alsa_cdsp

[adrii]

Hi Tim

Thanks for the suggestion. The install file only seems to install an executable. I don't know if the executable installs anything when run. The compressed archive didn't appear to include anything about the loopback device.

I also searched for 'snd-aloop' under "moode-player" at Github, but didn't get any results.

I remember some software installing the loopback device with only two subdevices, but I don't remember the name of the software or which player OS it was on.

Adrian.

[Tim Curtis]

Got it.

Maybe @bitlab, @seashell or @JWahle can help out. They are more familiar with the CamillaDSP components.

[JWahle]

For local testing, I initially configured CamillaDSP with the loopback device - but this was never released.
Nowadadays CamillaDSP uses the AlsaCDSP plugin, which does not use a loopback device.
AFAIK the loopback device is currently not used in moode.

You can verify this by connecting to your Raspberry via SSH and entering

Code:

aplay -l

If no device has the name "Loopback", it is not used.

[adrii]

Hi JWahle

Thanks for the extra details. I was looking for any projects or tutorials/instructions used with Moode that might install or uninstall the loopback device. However, now that Moode will be loading the loopback module any problems relating to shared use should be easier to deal with.

Adrian.