pyspectools2 2.0.8

A library for recording and plotting spectrograms from audio data.

Spectrogram Recorder Library

pyspectools2 is a Python library for recording audio, generating spectrograms, and managing numbered recording sessions.

Who this is for

This package is useful if you want a lightweight way to:

• record short audio clips from a microphone,
• visualize them as spectrograms,
• save outputs into incremental session folders.

Features

• Record audio from your default input device (sounddevice).
• Plot and save spectrograms (matplotlib).
• Create numbered session folders (session_1, session_2, ...).
• Delete the latest session and inspect folder sizes.
• Use a cross-platform default save location based on your home directory.
• Load, save, and process WAV files.
• Audio utilities: normalization, trimming, mono/stereo conversion.

Installation

pip install pyspectools2

Or from source:

git clone https://github.com/Ampter/pyspectools2
cd pyspectools2
pip install .

Runtime requirements

• Python 3.10+
• A working audio input device and backend supported by sounddevice
• Optional display backend for interactive plotting (headless CI can still run tests with mocks)

Quickstart

import pyspectools2 as pst

session_folder = pst.create_session_folder()
audio_data = pst.record_audio(duration=5)
fig, _ = pst.plot_spectrogram(audio_data)
output_file = pst.save_spectrogram(fig, session_folder)

print(f"Saved spectrogram: {output_file}")

Expected behavior:

• A folder like .../SOUNDS/spectrograms/session_1 is created.
• Console shows recording start/finish messages.
• A file named like spectrogram_Mon_Jan_01_12-00-00_2026.png is saved.

API reference

Session management

pst.get_default_directory()

Returns the default directory for spectrogram sessions:

• Windows: C:\Users\<username>\SOUNDS\spectrograms
• macOS: /Users/<username>/SOUNDS/spectrograms
• Linux: /home/<username>/SOUNDS/spectrograms

pst.create_session_folder(directory=None)

Creates a new folder such as session_5 and returns its path.

pst.get_latest_session_folder(directory=None)

Returns the highest numbered session folder path, or None if absent.

pst.delete_latest_session_folder(directory=None)

Deletes the latest numbered session folder.

Recording and plotting

pst.record_audio(duration=3, rate=44100, channels=1)

Records audio and returns a flattened NumPy array.

pst.plot_spectrogram(audio_data, rate=44100)

Returns (fig, ax) for the generated spectrogram.

pst.save_spectrogram(fig, session_folder)

Saves a PNG in the target session folder and returns the output file path.

WAV and Audio processing

pst.load_wav(path)

Loads a WAV file and returns (audio_data, samplerate).

pst.save_wav(path, audio_data, samplerate)

Saves a NumPy array to a WAV file.

pst.record_and_save_wav(duration=3, rate=44100, channels=1, directory=None)

Records audio and saves it as a WAV file in a new session folder.

pst.batch_process_wavs(directory)

Loads, normalizes, trims, and generates spectrograms for all WAV files in a directory.

pst.normalize_audio(audio_data)

Normalizes audio data to the range [-1, 1].

pst.trim_silence(audio_data, threshold=0.01)

Removes leading and trailing silence from audio data.

pst.to_mono(audio_data) / pst.to_stereo(audio_data)

Converts audio data between mono and stereo formats.

Storage utilities

pst.get_folder_size(directory=None)

Returns folder size in bytes.

pst.print_folder_size(directory=None)

Prints the total size of the latest session folder.

Common errors and fixes

• No audio input device available

  • Ensure your OS microphone permissions are enabled.
  • Verify input devices with your system audio settings.

• Permission denied when creating folders

  • Pass a writable path to create_session_folder(directory=...).

• Unsupported operating system error

  • get_default_directory() supports Windows, macOS, and Linux only.

Development

Run tests:

pytest

Test layout:

• tests/test_spectrogram.py: behavior of the library.
• tests/test_audio_processing.py: tests for audio utility functions.
• tests/test_wav_io.py: tests for WAV file input/output and processing.
• tests/test_versioning.py: release version bump rules.
• tests/test_packaging_metadata.py: packaging/version source-of-truth checks.

Examples

You can find examples in the examples/ directory:

• examples/basic_workflow.py: Basic script, same as in quickstart.
• examples/record_duration.py: Records and saves for a specified duration.
• examples/record_infinite.py: Infinitely records and saves spectrograms in a loop.
• examples/load_wav.py: Shows how to load a WAV and plot its spectrogram.
• examples/batch_processing.py: Demonstrates batch processing of multiple WAV files.

Contributing

Contributions are welcome.

License

This project is licensed under the General Public License. See LICENSE for details.