hertz

status: working. tested. api still in flux.

useful functions for working with frame-rates, sample-rates, other rates, time durations, frequencies, etc and for keeping a constant framerate. written in rust.

to use add hertz = "*" to the [dependencies] section of your Cargo.toml and call extern crate hertz; in your code.

read the documentation for an example and more !

contributing

licensed under either of apache-2.0 (tl;dr) or MIT (tl;dr) at your option

lib.rs:

useful functions for working with frame-rates, sample-rates, other rates, time durations, frequencies, etc and for keeping a constant framerate.

rate, sample rate, frame rate, fps, frequency, etc express the same concept and are therefore used interchangeably.

you can use hertz to compute the time resolution and frequency range that can be meaningfully analyzed by a short-time fourier transform of a signal:

extern crate hertz;

fn main() {
let sample_rate = 44100;
let window_size = 4096;
let step_size = 512;

// 11 hertz is the maximum frequency that can be meaningfully analyzed
assert_eq!(
11.,
hertz::rayleigh(sample_rate as f64, window_size as f64).round());

// 22050 hertz is the maximum frequency that can be meaningfully analyzed
assert_eq!(
22050.,
hertz::nyquist(sample_rate as f64).round());

// 12 ms is the time resolution we get when analyzing a 44100 hertz
// signal with a step size of 512
assert_eq!(
12.,
hertz::s_to_ms(hertz::cycles_per_second_to_seconds_per_cycle(
sample_rate as f64,
step_size as f64)).round());
}

you can use hertz to keep a constant framerate in a game or other computer graphics application:

fn main() {
let frames_per_second: usize = 60;

loop {
let instant_at_frame_start = std::time::Instant::now();

// here's where logic and rendering would go.
// this is never called more than frames_per_second
// times per second.

hertz::sleep_for_constant_rate(
frames_per_second, instant_at_frame_start);
}
}