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c++qtecho-cancellationvlc-qt

Mic/Speakers Audio Feedback in VLC API

I'm building a Webcam recording application with Qt 5.3 using vlc-qt, the problem is while previewing Audio/Video high feedback/noise and echo starts and gets higher, I've been googling and found it's the effect called Larsen's effect and how it's happening.

Notes:

  • I know using a headphone is a solution
  • I'm on a Windows 7 Ultimate Notebook
  • The Microphone Boost on zero dB is less noise but echo is persistent

My Questions:

  • How other webcam recording applications suppress the noise and the echo?
  • Specifically, how it can be fixed in VLC, your answer can be commandline arguments, notes or instructions to do in VLC software, it doesn't have to be code

Thanks!

Solution

  • I found http://www.dspcottage.com/en/algorithms/AEC a C++/MFC echo cancellation application based on Speex, but I needed to use it in Qt so I scrapped all MFC related code and here is the final solution https://github.com/Marware/Cpp_AEC