How do I output my audio input?

Question

A few iterations ago, I think this was Jaunty but could've been before, I would plug a 1/8" audio cable from the line-out of a Windows netbook to the line-in of my Ubuntu machine, so I would have all the sound from both machines without having to plug both into a mixer which I don't have. I didn't do this much, as I was pretty-much happy with Banshee at the time. But with Karmic, and still with Lucid, I can only get the output if I'm recording with Audacity. Which I'm not going to do from my web-development and systems programming workstation.

I can tell by plugging in headphones that my netbook has audio out working. I can see Sound Preferences that the Ubuntu machine is receiving them. I just want the old behavior back. Help?

score 22 · Accepted Answer · answered Aug 21 '10 at 12:17

22

If I understand correctly, you're trying to stream the microphone input to the audio output? The simplest I can think of is to use gst-launch for that. Open a terminal and type:

gst-launch pulsesrc ! pulsesink

The press CTRL+C to stop streaming. You may have to install the gstreamer tools to have this available:

sudo apt-get install gstreamer-tools

Note that as I don't have any suitable audio source, I didn't actually try that so it may not work. Any feedback on whether it does would be appreciated.

answered Aug 21 '10 at 12:17

Bruno Girin

516

It works quite alright.. – LasseLuttermann Aug 22 '10 at 14:27
That it does. I got the answer on the weekend and have the problem on my work machine, so I didn't want to say OK until I tested it. And I'm testinb it right now. It does work. – Dave Jacoby Aug 23 '10 at 12:19
Is this still the only fix? Nothing in the GUI? I'm running 13.04. – Corey Apr 22 '13 at 17:29
2

On my Linux Mint system, I have to use gst-launch-1.0 rather than just gst-launch. But the basic recipe works perfectly with that fix; +1. – steveha Jan 10 '16 at 22:34
1

On 16.04 this answer gives the error; ERROR: pipeline could not be constructed: no element "pulsesrc". – TenLeftFingers Dec 01 '16 at 19:45
My Ubuntu 18.04 can't locate the package gstreamer-tools... – OZ1SEJ Apr 16 '19 at 14:05
3

Ubuntu 19.04, preinstalled gst-launch-1.0, instead of gst-launch, if not just sudo apt install gstreamer1.0-tools, or look here – Wu Wei Sep 10 '19 at 18:56

score 4 · Answer 2 · answered Jan 29 '14 at 15:09

If you want to use existing pulse-audio tools, use pacat (which stands for pulse-audio cat).

get your input device with

pactl list
[...]
Source #0
        State: SUSPENDED
        Name: alsa_output.pci-0000_00_1b.0.analog-stereo.monitor
        Description: Monitor of Built-in Audio Analog Stereo
        Driver: module-alsa-card.c
[...]

copy the 'name' part and use it with pacat :

pacat -r --device=alsa_input.pci-0000_00_1b.0.analog-stereo | pacat -p --latency-msec=1

where as device is the name you copied before.

This will cost a bit of CPU time (3,3% on my machine).

You can also pipe some audio converting software in between to filter, or use it over the network.

For list of possible devices, one can run pactl list short | egrep "alsa_(input|output)" | fgrep -v ".monitor". — Mikko Rantalainen, Oct 01 '14 at 06:32

score 1 · Answer 3 · edited Apr 13 '17 at 12:24

1

Bruno Girin's answer worked for me as well, but manually launching a process is somewhat annoying as this should just be automatic. A better solution is to install gnome-alsamixer and unmute the line-in option, as described here:

No sound from line-in

edited Apr 13 '17 at 12:24

Community

1

answered Jul 09 '12 at 15:19

Nate

111
2

How do I output my audio input?

3 Answers3

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