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Torxed

Member

Registered: 2013-01-10

Posts: 203

Audio - Link Microphone and playback into one device?

Is it possible to merge two audiosources togeather in any nifty way?
Mainly interested in the default recording device (or otherwise specified) with the playback device.

I'm using JACK which i thought was able to do so but never got it working in any practical way al tho i enjoy playing around with it.

Why i want to do it is because i want ffmpeg to easily pick up two sources from one channel, and being able to switch around in say JACK would be awesome in real time not affecting the ffmpeg stream, considering i might be streaming something for a bit and want to switch audio source mid-stream to erm i dunno say a radiostation while i go off doing something else.

Linux is versatile so i bet it's possible, i just don't know how yet

Torxed

Member

Registered: 2013-01-10

Posts: 203

Re: Audio - Link Microphone and playback into one device?

I've got this partially solved:

#!/bin/bash
KEY=`cat key.db`

ffmpeg \
 -i http://pub1.di.fm:80/di_vocaltrance \
 -f alsa -ac 2 -i hw:0 -acodec mp3 -aq 1 -ab 128k \
 -f x11grab -s 1920x1080 -r 25 -i :0.0 \
 -c:v libx264 -preset fast -pix_fmt yuv420p -s 1280x800 \
 -c:a mp3 -ab 96k -ar 22050 \
 -threads 0 \
 -map 0:0 -map 1:0 -map 2:0 \
 -f flv "rtmp://live.twitch.tv/app/$KEY"

But now for the tricky part..
Everything sounds like i'm inside a tin-can for some reason (probably to do with the mixing, ffmpeg probably don't like that for the format?).

So i thought i'd give ffmpeg-full a go with jack support.
Giving me the option to link several inputs into one single channel making it a single-audio track in the video, also giving me the option to patch this by muxers and what not.. But it gives me this:

     -f alsa -ac 2 -i jack \
    ...

Produces:

[alsa @ 0x1399280] cannot set sample format 0x10000 2 (Invalid argument) jack: Input/output error