Atlas Audio: WAV Metadata Extractor

The WAV Metadata extractor reads Broadcast Wave Format (BWF/BEXT) metadata from WAV files to discover render provenance — which DAW project produced the file, what software rendered it, and when. It’s part of the Atlas Audio extractor pack.

Extension: .wav

How It Works

The extractor parses the RIFF/WAVE container to find the bext chunk, which is part of the BWF specification. DAWs like REAPER embed metadata in this chunk when rendering audio. The extractor reads fixed-size fields from the chunk and emits them as traits.

Non-BWF WAV files (those without a bext chunk) are silently skipped — no traits are emitted.

What It Extracts

The extractor produces traits only (no edges). WAV files don’t reference other files — they are referenced by project files. The traits provide provenance metadata that confirms where the file came from.

Trait	Source	Condition	Example
origin_project	BEXT Description field (256 bytes)	Only if the field starts with RPP:	/Users/me/Sessions/MySong.RPP
render_software	BEXT Originator field (32 bytes)	Non-empty	REAPER
render_date	BEXT OriginationDate + OriginationTime	Non-empty date	2026-03-11 21:49:46

Origin Project

REAPER writes the source RPP file path into the BEXT Description field, prefixed with RPP:. The extractor strips this prefix and records the full path as origin_project. Other DAWs may use this field differently — the RPP: prefix check ensures only confirmed REAPER provenance is recorded.

Render Software

The BEXT Originator field identifies the software that rendered the file. For REAPER renders this is REAPER.

Render Date

The BEXT OriginationDate (10 bytes, format YYYY-MM-DD) and OriginationTime (8 bytes) are combined into a single timestamp. REAPER uses hyphens in the time field (HH-MM-SS), which the extractor normalizes to colons (HH:MM:SS).

Confirmed vs. Suggested Provenance

The WAV Metadata extractor works in tandem with the Reaper extractor to provide two levels of provenance:

1. Suggested — The Reaper extractor finds a render output edge (RPP → WAV path). This tells Atlas where the project intends to render, but doesn’t confirm the file was actually produced by that project.

2. Confirmed — The WAV file’s BEXT metadata contains origin_project pointing back to the RPP. This confirms the file was actually rendered from that specific project.

When both are present, Atlas can trace bidirectionally with high confidence: forward from RPP to rendered WAV via the output edge, and backward from WAV to source RPP via the origin_project trait.

Example Usage

# Scan rendered audio
atlas scan ~/music/sessions/Renders/

# View metadata traits
atlas history ~/music/sessions/Renders/my-song.wav

Use Cases

• Render provenance — Confirm which DAW project produced a rendered file
• Bidirectional tracing — Trace forward from project to render, or backward from render to source project
• Render auditing — See when files were rendered and by which software
• Deliverable verification — Verify that a delivered file was rendered from the expected project