Article Proposal: Real-time noise suppression in PulseAudio

Hi everyone, I recently took a dive into real-time noise suppression capabilities on Fedora which can sometimes be really handy for video conferencing. The idea would be to explain how to set up PulseAudio for live noise-reduction using an LADSPA filter and this Copr redpository.

I can write that article. Given the recent uptake in video and audio calls, this might be of interest to a lot of people right now. What do you think?

  • Title: Real-time noise suppression in PulseAudio

  • Alternative title: Real-time noise suppression for video conferencing

  • Description: With people doing video conferencing all day, good audio has recently become much more important. The best option is obviously a proper audio studio. Unfortunately, this is not something you will always have and you might need to make do with a much simpler set-up.

    In such situations, a noise reduction filter that keeps your voice but filters out ambient noises (street noise, keyboard, …) can be very helpful. In this article, we will take a look at how to integrate such a filter into PulseAudio, so that it can easily be used in all applications with no additional requirements on their part.

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This sounds like it would be an excellent article for the magazine. +1 from me. I’d give it a +2 if I could!

I love this idea, big +1 from me as well.

+1 from me :slight_smile:

@lkiesow I created a Taiga card for you and added you to the board.

Thanks. I’ll try to finish the article over the next few days.
I’ll make sure to ask if something seems unclear about the process.

I was struggling with cleaning up recorded audio after meetup, and it would be nice to get a follow up article on how to do this for Audacity. Noise suppression as well as echo reduction. Sounds like a series. )

That would work and is probably not too hard. If this should become a series, there are also some other things that could be done:

  • Noise reduction in post processing
  • Echo canceling in video conferences (another PulseAudio plugin)
  • Video manipulation for video conferencing (e.g. including a logo) using v4l2loopback
  • Using DSLRs or other semi-professional cameras as webcam using GPhoto + v4l2loopback

I would like to add my +1. A series of articles would be welcome on the topics mentioned here.

Video and audio synchronization in post processing is also needed. I didn’t expect that two cameras and a separate mic for the same recording session will have different timestamps, but more surprising were stories that with different devices often the whole timing can be stretched.

I would also appreciate the low level comparison of PulseAudio latency vs JACK latency vs PipeWire. Low level means following how the audio data travels from mic to memory and back to speakers. Showing hexdumps of all memory areas on the way, and where the code that moves the data and processes it is executed. Is it possible to create sound accelerators that can take care of moving sound in parallel with CPU, etc.

The first draft of the noise reduction article is finished

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