result of FFT

[Andy Valencia]

On Wednesday, 9 July 2025 at 19:39:43 UTC, Matthew wrote:

> Checking the closest bins to each frequency seems to work well, 
> at least with clean sound from a wav file. It remains to be 
> seen how it fares against noisy real life signals. I'll likely 
> need a window function or interpolation but this is a good 
> start.

Many moons ago I had to fix Asterisk's DTMF detection/decode.  
Ultimately fixes (but not my code) made it into their source 
repo, and if you need guidance on a very mature DTMF treatment, 
main/dsp.c in the Asterisk source would be a solid resource.

Andy