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Comment by chungy | Hacker News Reader

Can someone give the quick tutorial on how to load music files into the thing? I installed projectm-sdl on Arch, it doesn't seem to do anything when I pass a file name to the program, keyboard mashing seems to do nothing, and dragging-and-dropping from a file manager seems to do nothing.

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You have to make sure to either feed it a microphone input or research how to set up a loopback monitor with pulsaaudio/pipewire/alsa (whichever you use). This way you can feed it whatever the audio output from any application. Then you many also need to specify an environment variable in your shell (I think it’s something like SDL_AUDIODRIVER I’m not sure and you set it to the specific driver you’re using) in any case you should be able to find instruction with “pulseaudio loopback stereo monitor sdl”

(Apologies for formatting i am on mobile)

I recently had to set this up on a raspberry pi 4 with manjaro / KDE plasma and it was a bit of a pain to setup (the setup is slightly different depending on your exact audio configuration) but it’s very rewarding once you do.

Feel free to PM as I spent a lot of time debugging the setup and may be able to help!

Thanks, that wasn't at all obvious... I had to figure out also how to get audio to redirect in Pipewire, but now I can actually see the output.

I suppose this thing would probably be more useful as an ffmpeg filter and/or audiacious plugin.

This is a fantastic idea! I forked [1] projectM a while back to work on a few modifications such as screen and audio recording (by saving raw framebuffers) and being able to select the active preset remotely from a web interface so I became somewhat familiar with the way projectm handles A/V input/output.

I just took a look at ffmpeg’s video filter interface and it looks like linking the two could be doable!

This feels like a much more elegant solution for recording frame-perfect captures so thank you!

I’ll definitely be looking more into it.

[1] https://github.com/hashFactory/projectm

IMO making a projectM-gstreamer plugin would accomplish this a lot easier and better. I wanted to do this but wasn't sure how to create the GL context. Started it a while back: https://github.com/projectM-visualizer/projectm/pull/207

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