MetaSona
Copyright 2026 MetaSona contributors
MetaSona author: Jiahua Zhang, September 2026.
Developed with assistance from OpenAI Codex.

The combined distribution is licensed under GPL-3.0 (LICENSE).
Original project material retains Apache-2.0 (LICENSES/Apache-2.0.txt).
Included adaptations retain the following upstream notices and terms:

ECMA Sottek Hearing Model loudness, roughness, tonality and shared primitives:
adapted from SQAT/RefMap code by
Mike JB Lotinga and Matt Torjussen, University of Salford, RefMap project
(www.refmap.eu), GPL-3.0; see LICENSE. SQAT revision
e6228b789fc9a22251314f95678b9b1e08e60c55. MoSQITo 2022 comparison coefficients
and algorithm by Eomys/contributors, Apache-2.0, revision
d990c33f94f1b2050b2d811dea492219ebe97b30. See LICENSES/Apache-2.0.txt.

PocketFFT — Copyright (C) 2010-2019 Max-Planck-Society; Martin Reinecke.
BSD-3-Clause; the complete notice is in LICENSES/BSD-3-Clause-PocketFFT.txt.
Pinned upstream C backend, integrated with call-local FFT plan reuse.

MoSQITo — Eomys and the MoSQITo contributors (Apache-2.0).
Zwicker loudness model data, roughness Bark/threshold/ear-transfer data,
and channel weighting. See LICENSES/Apache-2.0.txt and THIRD_PARTY.md.

SQAT loudness and third-octave filtering — Copyright (c) <2015>, <Ella Manor>.
Adapted for SQAT by Gil Felix Greco; later contributions by Sergio Aguirre.
BSD-3-Clause; the complete notice is in LICENSES/BSD-3-Clause-SQAT.txt.

SQAT Daniel–Weber roughness — copyright © 1999-2023 Dik Hermes.
Contributors include Matt Flax, Farhan Rizwi, Gil Felix Greco, Alejandro Osses
and Sergio Aguirre. Includes the MIT-licensed shared Terhardt filterbank.
MIT; the complete notice is in LICENSES/MIT-SQAT.txt.

PA/SQAT Aures tonality — Gil Felix Greco, 2020-2026; Sergio Aguirre, 2026.
The reused author-supplied psychohelperc tonality kernel derives from
Tonality_Aures1985.m and retains deterministic phase and per-tone masking.
The older PA adaptation retains BSD-3-Clause; see LICENSES/BSD-3-Clause-PA-Tonality.txt.
The current SQAT tonality port, including narrowband detection, is GPL-3.0;
see LICENSE. SQAT revision: e6228b789fc9a22251314f95678b9b1e08e60c55.

MetaSona changes: C11 APIs, per-call state, checked allocation and input
validation, immutable Python results, explicit framing, and model-specific
differences documented in THIRD_PARTY.md. These are adaptations, not upstream
releases. No endorsement or standards-conformance certification is claimed.
