# Zhen-Ni/epnl

> Part of [LISQM](https://zhenxianli.github.io/LISQM/) (List of Implementations of Sound Quality Metrics), a list of open-source implementations of psychoacoustic metrics. Data as of 2026-10-28. Web page: https://zhenxianli.github.io/LISQM/projects/zhen-ni-epnl.html

**Legacy project.** Not maintained. Its last commit was in July 2023, more than three years ago. Kept here for reference. Its code may follow an older edition and may not run with current software.

Small Rust crate that computes perceived noisiness (noy), perceived noise level (PNL) and tone-corrected perceived noise level (PNLT) from 24 one-third-octave band levels, citing ICAO Annex 16, Volume I, Appendix 2 in its code comments.

- **Repository:** https://github.com/Zhen-Ni/epnl
- **Language:** Rust
- **Kind:** Library/Toolbox (Functions to call from your own code: a Python package, a MATLAB toolbox, or a C, C++, C#, Rust or Julia library.)
- **Group:** legacy (Archived, or no commit for three years or more. Kept for reference. The code may follow an older edition and may not run with current software.)
- **Licence:** none
- **Latest release:** no release
- **Last commit:** 2023-07-10 (inactive since 2023-07)
- **GitHub stars:** 0
- **Maintainers:** Zhen-Ni
- **AI assistance:** not stated
- **How to cite:** The project does not say how to cite it. Cite the repository with the version or commit you used.
- **Entry checked:** 2026-10-06

## What it implements

| Metric | Edition | Functions | Status | Validation (as stated) | Notes |
|---|---|---|---|---|---|
| [Perceived noise level and EPNL](https://zhenxianli.github.io/LISQM/metrics/epnl.html) | [ICAO Annex 16, Vol. I](https://store.icao.int/en/annex-16-environmental-protection-volume-i-aircraft-noise) (PNL and PNLT only; no duration correction to EPNL) | `SPL`, `Noy`, `PNL`, `PNLT` | available | not stated | Code comments cite "Annex 16 - Volume I, APP 2-16 / 2-17" and number the 24 bands "consistent with ICAO ANNEX 16". The quantities are Rust types converted into each other with `From`. |

## How it was validated

As reported by the project; LISQM has not run the code. Two implementations that agree can still share the same error.

The project does not say how any of these were validated.

## Notes

- The crate (version 0.1.0) has no README and is not published on crates.io; input.txt holds two example 24-band spectra.

## Before you rely on it

- The GitHub description reads "Calculate Effective Perceived Noise Level (EPNL) for aircrafts", but EPNL itself is not implemented: there is no time integration or duration correction.
- No licence file, so reuse is not permitted by default.

## Sources

- https://github.com/Zhen-Ni/epnl
- https://github.com/Zhen-Ni/epnl/blob/master/Cargo.toml
- https://github.com/Zhen-Ni/epnl/tree/master/src