Believeyoume validation · P2 of P1–P5 · 2026-07-07

Section boundary detector — Asleep In The Trunk

Reads P1 per-beat records and finds section boundaries using chord-stability + vocal-density signals. Feeds P3 claim ledger (per-section harmonic claims from the model rebuild).

Song header

173.0

BPM

3/4

Time sig

Bars

Sections

Verse blocks

Chorus blocks

Non-vocal blocks

Section timeline

O10

Sections detail

#	Kind	Bars	Time	Beats	Vocal density	Gtr density	Chord changes	Bass root signature
s00	intro	1–8	0.0s – 8.0s	24	0.08	0.12	17	C → D# → F → C → D# → F → C → D# → F → C → D# → F → C → D# → F → C → F → C
s01	verse	9–12	8.3s – 12.1s	12	0.92	1.0	6	C → F → C → F → C → F → C
s02	break	13–14	12.5s – 14.2s	6	0.17	0.17	0	C
s03	verse	15–20	14.6s – 20.5s	18	1.0	0.0	13	C → D# → F → C → D# → F → C → D# → F → C → D# → F → C → D#
s04	break	21–22	20.8s – 22.5s	6	0.33	0.0	0	F
s05	verse	23–34	22.9s – 35.0s	36	0.86	0.86	3	F → C# → A# → G#
s06	instrumental	35–42	35.4s – 43.4s	24	0.04	0.71	1	G# → F
s07	verse	43–48	43.7s – 49.6s	18	0.83	0.83	3	C# → A# → G# → F
s08	break	49–50	49.9s – 51.7s	6	0.17	0.17	0	F
s09	verse	51–52	52.0s – 53.8s	6	1.0	1.0	0	C
s10	outro	53–55	54.1s – 56.2s	7	0.0	0.86	0	F

Notes on labeling

Chorus detection needs a repeated signature. The current heuristic labels a vocal-heavy block "chorus" only when the same ordered bass-root pattern appears in at least two blocks. Asleep's five vocal blocks show four distinct signatures, so all resolve to "verse" here. P3 or a human pass can re-label if the song's actual chorus is repetitive at a longer bar window than 2.
Break vs instrumental: low-vocal blocks with guitar density ≥ 0.5 are "instrumental"; below that they are "break". Intro is the leading non-vocal block; outro is the trailing one.
Bridge: only fires when a chorus has already appeared, the block sits in the middle, and a new signature shows up. Not fired here because no chorus was detected.
Fixed window: 6-beat (2-bar) analysis windows. A song in a different meter will need a different window.

Artifacts

Detector: ~/Projects/_outputs/believeyoume-midi/section_detector.py
Sections JSON: ~/Projects/_outputs/believeyoume-midi/asleep-in-the-trunk_sections.json
P1 beat feed: ~/Projects/_outputs/believeyoume-midi/asleep-in-the-trunk_beatwalk.json

Kid mode 🧒

Song header

Section timeline

Sections detail

Notes on labeling

Artifacts