Nightly routine

• 1 Enable Camera — pick the Logitech. Aim it at the bench; every dashcam screen must be visible.
• 2 Choose Save Folder — a night_… folder is created per session (video chunks, snapshots, events.json, report).
• 3 Add Units (QR) — hold a unit's QR code up to the camera → beep, serial captured. Then place the unit on the bench: the system finds where the new screen lit up and draws an outline with the serial (double beep). The outline is stretched sideways to cover the long dashcam body (adjust Outline stretch × in settings); detection itself watches only the screen inside it — shown as a white dashed box when you select a unit. Repeat for every unit, in any positions — the number is just the sequence you added them.
• 🎨 Calibrate all units (once all screens are on, before Start Monitoring) — measures each unit's own lit brightness and black bezel and gives it its own OFF/ON thresholds. Do this on a full rack: far or angled screens read dimmer than near ones, and one global threshold can leave a far unit's lit screen hovering near "OFF". Units show 🎨off/on in the Units table; Clear calibration returns to the global thresholds.
• If an outline lands wrong: click it → Remove, then use Draw outline manually (drag a box around the screen) — it takes the pending serial. You can also drag/resize a selected outline.
• 4 Start Monitoring — leave the tab open and in the foreground all night; the page keeps the screen awake. Point the monitor away from the bench or dim it.
• Morning — Units / Report: clean units are done; flagged units have timestamped events + snapshots in the night folder for the DMD warranty claim.
• Event clips (parking-surveillance style) — at End Night the system cuts a short clip around every fault (default 60 s before → 60 s after) into clips/: full bench view with the unit outlined, a zoomed inset of that unit, and a T−/T+ counter. Each clip takes as long as its length to make, so End Night waits ~2 min per fault. Press ▶ clip in the Events tab to watch one, 🎬 to cut one right away, or Make clips from a night folder… for a past night (works even if the tab crashed before End Night).

QR scanning tips

• The 70mai serial sticker QR is tiny (~15 mm): bring it into the orange center box, about 10–15 cm from the lens, flat and steady, and watch the zoom-check window (top-right) — when the QR looks sharp there, it scans within a second. Tilt slightly if the glossy label glares.
• Check the scan line says camera 3840×2160. If it shows 1920×1080 with a 4K camera, plug it into a USB 3.0 port (blue) — on USB 2.0 many 4K cams fall back to 1080p, and the tiny QR becomes unreadable.
• The same code won't scan twice in a row (6 s cooldown).
• Place the unit within ~30 s of scanning, and keep your hand out of view once it's placed — the outline locks on after the new screen stays put for ~3 s.
• Scanning uses Chrome's built-in detector when available, otherwise the bundled jsQR.min.js — keep that file next to this page.
• You can also type a serial + Enter instead of scanning, then place the unit the same way.

Windows / Chrome setup (one time)

• Settings → System → Power: set Screen off = Never and Sleep = Never (at least for test nights).
• Use Chrome or Edge. Keep this tab focused overnight — background tabs get slowed down and detection would miss events.
• Disk: default settings use roughly 8–12 GB per 12-hour night. Delete old night_… folders when done with the claims.
• Glossy/acrylic display tiers: line each tier with dark matte material (black cloth / EVA foam). Heat-lamp reflections on shiny acrylic look like lit screens to the detector; a dark matte base kills the glare and makes real screens stand out.

What the events mean

• AUTO_OFF — the screen went dark and stayed dark.
• RESTART — dark, then back on (auto restart). The off-duration is logged.
• STUCK_STATIC — screen bright but frozen (no ticking timer) — stuck at 70mai logo or hung.
• GLITCH — abnormal sudden picture change while on. Check the snapshot; tune the threshold if it fires too much.