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
