Sampled Data Duration

Rust library for handling durations of sampled data, e.g. digital audio.

The sampled_data_duration crate provides two stucts: ConstantRateDuration and MixedRateDuration.

A ConstantRateDuraiton can be used to represents the duration of any data-set which has been sampled at a constant frequency, a prime example might be an audio file sampled at 44.1kHz.

A MixedRateDuration can be used to represent the duration of a collection of data-sets which have different sampling frequencies. A typical example might be a playlist of audio files where some have been sampled at 44.1kHz, and others at 48kHz or 96kHz, etc.

Example

use sampled_data_duration::ConstantRateDuration;
use sampled_data_duration::MixedRateDuration;

// Consider an audio file which consists of `12345678` samples per
// channel recorded at a sampling rate of 44.1kHz.
let crd = ConstantRateDuration::new(12345678, 44100);

// The default string representation is of the form
// `hh:mm:ss;samples`
assert_eq!(crd.to_string(), "00:04:39;41778");

// Get the duration in various different time-units
assert_eq!(crd.as_hours(), 0);
assert_eq!(crd.as_mins(), 4);
assert_eq!(crd.submin_secs(), 39);
assert_eq!(crd.as_secs(), 4 * 60 + 39);
assert_eq!(crd.subsec_samples(), 41778);
assert_eq!(crd.subsec_secs(), 0.9473469387755102);

// Consider and audio playlist which already consists of a file
// recorded at 96kHz.
let mut mrd = MixedRateDuration::from(ConstantRateDuration::new(87654321, 96000));

// The default string representation of the a mixed rate duration
// which consits of only one entry is of the form `hh:mm:ss;samples`
assert_eq!(mrd.to_string(), "00:15:13;6321");

// However if we add-assign `crd` to `mrd`
mrd += crd;

// Then we have a duration which is made up of different sampling
// rates and the default string representation changes to be of the
// form `hh:mm:ss.s`
assert_eq!(mrd.to_string(), "00:19:53.013190688");

An attempt has been made to follow the naming conventions defined by std::time::Duration.