ZPE-Prosody

Deterministic prosody packet encoding for speech F0, energy, duration, and voiced-mask contour bundles. The ZPRS/v1 codec compresses prosodic feature arrays to 13.0× on real LibriSpeech speech with 0.64% voiced-F0 RMSE and 2.67 ms mean encode latency — byte-stable, round-trip lossless within CI thresholds, no GPU required.

ZPE-Prosody is one of seventeen independent encoding products in the Zer0pa portfolio; it targets speech-technology and voice-analytics teams that need deterministic, reproducible prosodic feature encoding.

Licensed under the Zer0pa Source-Available License v7.0.

Commercial Readiness

No lane pass is claimed. No public release tag has been issued. The codec is useful as a deterministic encoding primitive; end-to-end commercial deployment requires resolving the gates above.

CI-Anchored Claims

Measured Performance (Proof-Artifact Records)

These metrics come from committed proof-artifact runs, not reasserted per CI push. Each number is anchored to a specific artifact file; the artifact commit is the evidence. CI thresholds are broader than these measured values by design — the proof runs set the floor, CI guards against regression.

Compression (baseline: raw float32 arrays for F0, energy, duration, voiced_mask)

Fidelity (round-trip encode → decode)

Encode latency (single-threaded, no GPU)

Robustness (malformed-packet falsification campaign)

Non-Promoted Historical Artifacts

The following proof artifacts remain in the repository for audit lineage, but their exact claims are not promoted in this README:

• proofs/artifacts/2026-02-20_zpe_prosody_wave1/before_after_metrics.json
• proofs/artifacts/2026-02-20_zpe_prosody_wave1/prosody_retrieval_eval.json (PRO-C006: FAIL — p@5=0.31 vs threshold 0.80)
• proofs/artifacts/2026-02-20_zpe_prosody_wave1/quality_gate_scorecard.json (overall gate FAIL; PRO-C005 PAUSED_EXTERNAL (blocked on external dependency), PRO-C006 FAIL)
• proofs/artifacts/c006_retrieval_failure_analysis.md
• proofs/artifacts/c005_replacement_analysis.md

What Is Not Claimed

• No lane pass.
• No retrieval closure above threshold.
• No commercialization-safe transfer closure.
• No public release-readiness claim.
• No speech-codec comparator leadership vs production systems.
• No MOS claim — transfer evaluation was not executed end to end with a commercially safe transfer stack.

Repo Shape

• src/zpe_prosody/: installable codec package.
• tests/: CI-backed package, packet, API, and round-trip checks.
• scripts/verify_release_surface.py: package surface sanity helper used by make package-sanity.
• proofs/: historical adjudication artifacts and audit lineage.
• docs/: architecture, legal-boundary, market-surface, and family notes.

Quick Start

python -m venv .venv
source .venv/bin/activate
python -m pip install -e ".[dev]"
make repo-sanity
make package-sanity
make test

Optional API wrapper dependency:

python -m pip install ".[api]"

The base wheel ships only src/zpe_prosody. No CLI or historical gate harness is packaged as a runtime contract. Read docs/LEGAL_BOUNDARIES.md before widening any claim from this repo state.