Homecage Camera Control

Some setups connect two homecages through the corridor, with animals able to move between them. AREA_EXTRA is a 5th, special corridor detection area (on top of the regular AREA1_CORRIDOR-AREA4_CORRIDOR) used to check that the passage between the two homecages isn’t physically blocked (e.g. by bedding, an animal staying put for hours, or a mechanical issue) for longer than expected.

It’s off by default, and everything about it is opt-in.

Enabling it

In SETTINGS -> ADVANCED SETTINGS, turn CORRIDOR_AREA_EXTRA ON. This reveals a second setting, AREA_EXTRA_HOURS: the size, in hours, of the window used to decide whether the passage has been blocked for “too long” (see Occupation alarm below).

Note

Like the other corridor/box camera options, CORRIDOR_AREA_EXTRA takes effect for the MONITOR tab described next after restarting the app.

Configuring the area

Once active, a new EXTRA tab appears in MONITOR, alongside INFO, PLOT and DETECTION SETTINGS. It shows:

  • empty limit — same idea as the DETECTION SETTINGS tab’s mouse-detection limits, but only the empty/not-empty threshold: this area only cares about whether the passage is blocked, not how many subjects are in it, so there’s no subject limit control here.

  • View detection corridor — the same VIEW_DETECTION_CORRIDOR toggle already in DETECTION SETTINGS (changing it here changes it everywhere; it’s just exposed in both places for convenience).

  • AREA_EXTRA_CORRIDOR position and threshold controls — left, right, top, bottom, and day/night detection thresholds, exactly like AREA1_CORRIDOR-AREA4_CORRIDOR in DETECTION SETTINGS. Position the rectangle over the passage between the two homecages.

When active, the area is drawn on the corridor camera feed in a vivid violet rectangle (COLOR_EXTRA, editable in SETTINGS -> ADVANCED SETTINGS -> VISUAL SETTINGS, alongside COLOR_AREA1-COLOR_AREA4, once CORRIDOR_AREA_EXTRA is ON) — deliberately different from the 4 regular areas’ colors, so it stands out against any background.

Occupation alarm

While AREA_EXTRA is active, every camera frame is checked: if the area’s detected pixel count is above empty limit, that frame counts as “occupied” (blocked). Once every AREA_EXTRA_HOURS hours, the system checks what fraction of frames during that window were occupied — if more than 90%, it raises a repeating alarm:

Communication between homecages has been closed for more than N hours

The alarm repeats (like other repeating alarms) until acknowledged, either from the Telegram button or the ALARM button in the GUI. The occupied/total frame counters then reset and a new AREA_EXTRA_HOURS window starts.

Note

This is independent from CORRIDOR_OCCUPATION_ALARM (areas 1-4’s own >90%-of-the-last-hour check) – AREA_EXTRA always uses its own window length (AREA_EXTRA_HOURS), not the fixed 1 hour used for the other 4 areas.