Remove a specific frequency from mp3 file

Question

I'm wondering what methods are available to remove a specific frequency from an mp3 or wav file using C#.

I'm hoping for a library or example where I can input an mp3 ( or any other format, ill convert my soundtrack to whatever format is needed) and a single frequency (or list of frequencies) to remove from the file.

If there are no methods of doing this in C# I'll accept solutions using other languages as well.

I prefeer solutions using free or open source libraries.

Answer 1

I would suggest converting your MP3 to PCM, then using a time-domain filter.

A basic approach would be to use the notch filter described here:

http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt

with an implementation like this:

http://musicdsp.org/showArchiveComment.php?ArchiveID=174