Frequency detection crate

I've needed to detect a frequency of an audio signal a couple of times in my life, but I cannot for the love of me remember what does the FFT output actually mean. So I took this knowledge out of my latest project and packed it up in this crate.

Also this is my first potentially useful published crate, so if I missed anything, please let me know!

21 points · 6 comments · view on lemmy.world

6 Comments

BB_C@programming.dev · 10 pts · 2y (5 replies)

    /// # Panics
    ///
    /// - if `samples.len()` does not match the `sample_count` passed to [Self::new]
    /// - if there are `NaN`s in the sample slice

Since this is library code, why not make the function return a Result?

Traister101@lemmy.today · 7 pts · 2y (1 reply)

Yup, libraries should usually let the consumer chose what to do with an error, not crash the program without a choice in the matter. The only real exception is performance critical low level code such as the core of a graphics or audio driver. Though in those cases crashing also often isn't an option, you just power through and hope things aren't too screwed up.

fil@programming.dev · 2 pts · 2y

Thanks for the tip! Updated

anton@lemmy.blahaj.zone · 3 pts · 2y (2 replies)

The new version seems to fix that since your comment was written, but it will stil panics if less than 2 samples are provided, unless the crate it wraps panics at an earlier point.

let peak = buf
            .iter()
            .copied()
            .enumerate()
            .take(self.sample_count / 2)
            .max_by_key(|(_, s)| (s.abs() * 1000.0) as u32)
            .expect("to have at least 1 sample");

BB_C@programming.dev · 3 pts · 2y (1 reply)

You should have mentioned OP.

@fil

fil@programming.dev · 2 pts · 2y

Excellent catch! Added validation for the new params