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A comment on The vocal effects of Daft Punk. Parent comment

Re:The vocal effects of Daft Punk by jschafer on Monday May 05, 2025 @10:54AM (#43895773)
Yes exactly, I was really excited when I found out that you do not need a FFT to do speech processing.

If you look at the code of (phone/voice) codecs GSM/Speex/Opus you can see that you can estimate the spectral envelope (or the configuration of a physical tube model for the vocal tract) in time domain with linear prediction coefficients (LPC).

And it is simple, e.g. the often used Levinson-Durbin algorithm is just 22 lines of C code. It is an interesting exercise to build your own vocoder from scratch that fits in a single screen page.

Many of the code snippets I have seen (which likely have already processed your voice) are just translations of the Fortran code of the book "Linear Prediction of Speech" by Markel and Gray (1976).

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Re:The vocal effects of Daft Punk by nonrandomstring on Monday May 05, 2025 @02:12PM (#43897801)
Ah yes, ladder or lattice filters. If you don't mind old fashioned mailing lists there's still a few of hanging around in [email protected] where code gets shared.
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