soundlevelmeter 1.0.0

IEC 61672-1 Sound Level Meter

soundlevelmeter

An IEC 61672-1 and IEC 61260-1 compliant sound level meter in Python. Measures LAeq, LCeq, LZeq, LASmax, LAFmax, octave-band levels (1/1, 1/3, 1/6, …), sound exposure levels (LE), and more — from WAV files, a numpy array or a live microphone.

Features

• Broadband metrics — A/C/Z frequency weighting; Fast/Slow/Impulse time weighting; Leq, max, min, sound exposure level, and moving-window variants.
• Octave-band analysis (RTA) — arbitrary N/M-octave filter banks (1/1, 1/3, 1/6, …) per IEC 61260-1.
• Any source — WAV files, an in-memory NumPy array or a live audio device.
• Standards-based — filters and weightings verified against the IEC 61672-1 / 61260-1 conformance limits (scripts/conformance_report.py).
• Three ways to drive it — a command-line tool, an interactive REPL, and a Python API.

Installation

git clone https://github.com/ninoblumer/python-soundlevelmeter
cd python-soundlevelmeter
python -m venv venv
source venv/bin/activate      # macOS / Linux
# venv\Scripts\activate       # Windows
pip install -r requirements.txt

To use slm as a shell command instead, you can install this tool directly. For example with pip install --user git+https://github.com/ninoblumer/python-soundlevelmeter.git@main

Quickstart

Measure a recorded WAV file:

# calibrate from a recording of a calibration tone
$ python -m slm --file calibration.wav -- calibrate
Sensitivity: 17.68 mV  |  -35.05 dBV
$ python -m slm --file recording.wav --sensitivity-dbv -35.05 --measure LAeq LAFmax LCeq LZeq:bands:63-8000

Broadband results land in output/measurement_report.csv (and a per-dt _log.csv); per-band results in output/measurement_rta_report.csv. See Getting started for live input, the REPL, sensitivity flags, and every option.

Documentation

Full documentation lives in docs/:

Guide	What it covers
Getting started	CLI usage, live input, the generator, the interactive REPL
Metric name syntax	How to name quantities (LAeq, LAFmax_dt, LZeq:bands:63-8000, …)
Calibration	Deriving controller sensitivity from a calibrator tone
Signal conditioning	The XL2-style input filter (--signal-conditioning)
Configuration	TOML config schema for reproducible runs
Python API	High-, mid-, and low-level library entry points
Architecture	Controller → Engine → Bus → plugins → meters → Reporter
Running the tests	pytest, slow tests, the conformance margin report
Real-time load benchmark	Measuring CPU headroom against the real-time budget

License

This project is licensed under the GNU General Public License v3.0. See LICENSE for full details and NOTICE for third-party attributions.