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Masks

A mask marks part of a camera view so that GC Surge stops watching it. The Mask Editor describes its own job as “Draw timed or camera masks on the preview to control which areas are monitored.” Use it when a fixed part of the frame keeps producing alarms you do not care about — a swaying tree, a neighbour’s driveway, a busy public pavement, a flickering light.

Timed Mask and Camera Mask

The editor offers two kinds of mask, and turning one on turns the other off — a camera uses one or the other, never both at once.

  • Timed Mask — a temporary mask for a situation that will pass, such as contractors working in view for the afternoon. Turning it on reveals a Select Timer dropdown with three durations: 30 Minutes, 1 Hour, and 2 Hours. The mask lifts by itself when the timer runs out, so nobody has to remember to undo it.
  • Camera Mask — a permanent mask for something that will always be in shot, such as a road at the edge of the frame. It stays until somebody clears it.
Screenshot 2026-07-20 104811-20260720-074812.png

Opening the Mask Editor

  1. Open Video Search from the sidebar.
  2. Open any event from the camera you want to mask.
  3. Click Mask below the clips. The editor opens on a still from that event, so you are drawing against the exact scene that raised the alarm.

Drawing a Mask

The editor has two drawing modes, and the button at the top left switches between them — it is labelled with the mode you will move to, so it reads Pixel View while you are drawing polygons and Polygon View once you are in the grid.

  • Polygon view — draw free-form shapes that follow the thing you are covering. Each polygon appears in blue with a handle on every corner, so you can reshape it afterwards. Two extra tools appear in this mode: Undo steps back through your changes, and Smooth tidies a rough outline.
  • Pixel view — a red grid covers the whole frame and you switch individual cells on and off. This is the quicker choice for a broad rectangular area such as a whole upper corner of the view.

Clear in the toolbar removes everything you have drawn and starts the mask again.

  • Polygon view:
Screenshot 2026-07-20 111358-20260720-081359.png
  • Pixel view
Screenshot 2026-07-20 111349-20260720-081350.png

Editing Shortcuts

The information icon in the toolbar opens a Shortcuts panel listing every action available while editing:

ActionShortcut
Undo last changeCtrl + Z
Delete selected polygonsDelete
Select all polygonsCtrl + A
Invert selectionCtrl + I
Add a new polygonClick
Add a vertex on an edgeDouble-click edge
Remove a vertexDouble-click vertex
Move polygons or verticesDrag
Box-select polygonsDrag empty area
Add or remove from selectionShift + click

Saving and Removing a Mask

Click Save to apply the mask to the camera. The button beside it depends on what is already there: it reads Cancel when the camera has no mask yet and closes the editor without changing anything, and Clear when a mask already exists, which removes it.

Mask a region only when you are sure nothing worth an alarm can happen there. A mask that covers a doorway or a boundary line will silence real intrusions as well as nuisance movement.

Finding Masked Events

In Video Search, the Overlay filter in the Additional filters panel narrows the list to alarms carrying a particular visual analysis overlay — Heatmap, Mask, or History Mask. The Mask button in the event detail panel turns the overlay on and off while you review a clip, so you can see what the camera was ignoring at the time.