Root causes found:
1. Scheduler crashing every 15s: assets table has no error_message column.
Fix: remove error_message from UPDATE in scheduler.js (#66 regression).
2. Clip freezing: client-side filmstrip seek loop runs on main thread,
seeks same proxy the player is streaming → both stall → freeze.
Fix: replace browser seek loop entirely with server-side FFmpeg worker.
3. No dedicated filmstrip worker: filmstrip was never pre-built server-side.
Changes:
- services/mam-api/src/db/migrations/018-add-filmstrip-s3-key.sql
Add filmstrip_s3_key TEXT column to assets table
- services/worker/src/workers/filmstrip.js (new)
BullMQ worker: downloads proxy, runs FFmpeg fps filter to extract
28 evenly-spaced JPEG frames, base64-encodes them, uploads JSON
array to S3 at filmstrips/<assetId>.json, stores key in DB
- services/worker/src/workers/thumbnail.js
Queue filmstrip job automatically after thumbnail completes
- services/worker/src/index.js
Register filmstrip worker (concurrency=2), export filmstripQueue
singleton, close it on SIGTERM
- services/mam-api/src/routes/assets.js
- filmstripQueue added
- POST /reprocess?type=filmstrip now supported
- GET /:id/filmstrip returns signed S3 URL for JSON frames
- services/mam-api/src/routes/jobs.js
filmstrip queue visible in Jobs UI
- services/web-ui/public/screens-asset.jsx
Replace browser seek loop with fetch of /assets/:id/filmstrip
→ fetch S3 JSON → render frames. Zero browser-side video seeking.
Right-click and Files tab re-generate via API endpoint.