Use mp3 as input

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MontyZuma
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Joined: Sat Apr 01, 2017 11:11 am
Real Name: Klaus Muth

Hi!
I'm trying to test the Audio trigger functionality. Since I have no audio input at the moment I would like to use an mp3 recording as input.

Is there any way to do that?

klaus
janosvitok
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Depends on the OS you use.

Linux: check out alsa loopback device. Start player with output to loopback, set QLC+ to use alsa loopback as input.
OSX: I assume Core Audio has similar facility
Windows: It may be possible to instruct QLC+ to use the overall mix as input. In that case, you need to start normal player.
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MontyZuma
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Real Name: Klaus Muth

I'm posting in Linux specific - it's safe to assume I'm on Linux. :D

But I very much appreciate this full answer - I'll get some info about alsa loopback devices. I might report back my experiences.

klaus
janosvitok
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Sorry, I didn't notice the forum :)
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MontyZuma
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Joined: Sat Apr 01, 2017 11:11 am
Real Name: Klaus Muth

Solution for Ubuntu/PulseAudio:
  1. Install pavucontrol

    Code: Select all

    sudo apt install pavucontrol
  2. Open a shell and load the PulseAudio loopback module:

    Code: Select all

    pactl load-module module-loopback
  3. Start qlc+ and use audio standard input, add an audio control and start up the whole stuff
  4. Start audio playback
  5. Start pavucontrol and in the Record Tab find ALSA Plug-In qlcplus and select Monitor of internal Audio
    Beware: qlc+ only shows up in the Record Tab of pavucontrol, when the Audio Trigger is switched on!
    Image
YMMV - Works for me. (Sorry for the Screenshot in German)

The right keyword for your own search: pulseaudio loopback or alsa loopback.
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mcallegari
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Thanks for sharing :thumbsup:
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MontyZuma
Posts: 39
Joined: Sat Apr 01, 2017 11:11 am
Real Name: Klaus Muth

MontyZuma wrote: Mon Apr 03, 2017 9:05 am
  1. Open a shell and load the PulseAudio loopback module:

    Code: Select all

    pactl load-module module-loopback
It's possible to add the module in the system-wide config file: /etc/pulse/defauld.pa so you don't have to use a shell every time you want to use a mp3 as an audio input.
MDSurveyor
Posts: 6
Joined: Fri Jan 26, 2018 8:29 pm
Real Name: Joel Brengle

MontyZuma, thank you for your detailed answer. You seem very knowledgeable regarding Linux and QLC+. I love the program and I am having a similar problem with Audio but I am not sure if it is a Linux issue or a QCL+ issue. I had also posted in the general section yesterday, but I can't find the post! Oh well, new to the forum and probably did something wrong.

Anyway, my goal is to set the time of the duration widget for a chase from the tempo of a snare drum.

I have found the Audio tab and am able to select the input - I assume that I have the correct input selected because at the bottom of that section there is a small "play" icon and when clicked a level meter indicates incoming audio. When I go to the Virtual Console page and create the Audio widget I, it shows no signal. Also there is no audio level fader in the widget. I Do not understand what I am missing.

QLC Session Configuration:
Universe 1: All lights, INPUT from external MIDI foot controller
Universe 2: Passthrough, No lights, INPUT from OSC for remote iPad control
Universe 3 & 4: Nothing

OS: Linux Mint 18.1 Cinnamon

PC: Lenovo T61, 8GB RAM, NVIDIA graphics, Audio Device displayed in QLC is HDA Intel - AD1984 Analog

Thanks in advance for either helping or pointing me to the answer.

Joel
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