festifun/plan/status/lane-A.md

Status — lane-A

Round 0 — 2026-07-16 — STATUS: ready_to_merge (committed on isolated worktree)

Directives acknowledged: round 0 of plan/DIRECTIVES.md (run order & protocol; Lane A = spec M1).

Acceptance checklist (spec M1 + lane brief) — ALL PASSING:

• ingest: ffprobe each file in data/raw, register in videos, extract mono 16 kHz WAV into data/work/audio/.
• sync: PHAT-whitened GCC-PHAT pairwise offsets, scored by peak-to-second-peak ratio; sub-sample parabolic peak refinement.
• Global confidence-weighted least-squares solve; cycle-consistency rejection (>50 ms residual).
• Drift: windowed GCC-PHAT + line fit → drift_ppm; store 0 if |drift| < 5 ppm.
• Disconnected components → offset_ms = None (spec pitfall #5).
• Persist via db.update_video_sync; export config.SYNC_JSON.
• synthetic → ingest → sync recovers GT offsets (err < 0.001 ms) and drift 0 ppm — inside ±10 ms / ±3 ppm.
• pytest green in isolation: 43 passed (24 foundation + 19 new) on pristine foundation + Lane A only.

Done this round: implemented ingest.py + audio_sync.py; wrote test_ingest.py (6) + test_audio_sync.py (13). Committed as 157c783 on lane/a-media, based directly on main/foundation (5fa7301) — exactly the 5 owned files, no other lane's changes. Evidence (run in the isolated festifun-laneA worktree):

• pytest → 43 passed, 4 warnings (warnings are librosa/audioread deprecations only).
• synthetic → ingest → sync → DB cam0/1/2 = +0.000 / +1370.000 / −842.000 ms, drift 0, err ≤ 0.0002 ms vs ground_truth.json.
• sync exported data/work/sync.json (reference id, per-video offset/drift/confidence, raw edges, components).

Coordination note (was a blocker; resolved for Lane A): Lanes A/C/D were sharing one working directory (/Users/m3ultra/Documents/festifun) and colliding — HEAD there was moved to lane/d-events, and the shared tree held four lanes' uncommitted changes intermixed. Per coordinator sign-off, Lane A was landed into its own git worktree (festifun-laneA, branch lane/a-media reset to main) and committed there, disturbing no other worktree. Still open for coordinator: lanes C and D also need their own worktrees (lane B already has one); the shared dir still contains their intermixed uncommitted work.

Next: awaiting coordinator go-ahead to git push origin lane/a-media and merge to main (merge is coordination-sensitive given the collision; branch is ready).