impiir

Digital filter design for Rust.

Features

• Filter design — digital IIR filter generation matching industry-standard algorithms:
  • Butterworth — maximally flat passband, no ripple
  • Chebyshev Type I — equiripple passband, sharper rolloff than Butterworth
  • Chebyshev Type II — flat passband, equiripple stopband

Design a filter and apply it

use impiir::{ButterworthFilter, SosFilterBuilder, FilterPadding};

// Design a 4th-order Butterworth lowpass at 100 Hz (fs = 1000 Hz)
let sos = ButterworthFilter::new(4)
    .lowpass(100.0)
    .sample_rate(1000.0)
    .sos()?;

SOS vs BA

Always prefer SOS output (.sos()) over BA (.ba()) for orders above 4. The second-order section representation avoids the numerical precision issues that accumulate when multiplying high-order polynomial coefficients together.

This project is licensed under either of

• BSD-3-Clause License (see LICENSE)
• Apache License, Version 2.0 (see LICENSE)

at your option.