The sensitivity of DMSS (likely referring to a Dahua Mobile Surveillance System or similar) is a configurable setting, typically ranging from 0 to 100. A higher sensitivity value makes it easier to trigger alarms.
Understanding DMSS Sensitivity
DMSS, often used in conjunction with security cameras and recording systems, incorporates motion detection functionality. The "sensitivity" setting controls how readily motion detection alarms are activated. Here's a breakdown:
- Range: The sensitivity is usually set on a scale of 0 to 100.
- Higher Sensitivity (closer to 100): The system becomes more sensitive to motion. Even small movements can trigger an alarm. This is useful for detecting subtle activity but can also lead to false alarms caused by things like changes in lighting, shadows, or small animals.
- Lower Sensitivity (closer to 0): The system becomes less sensitive to motion. Larger movements are required to trigger an alarm. This reduces the likelihood of false alarms but may also cause the system to miss smaller, but potentially important, events.
Factors Affecting Optimal Sensitivity
The ideal sensitivity setting depends on several factors, including:
- Environment: An environment prone to frequent changes (e.g., windy conditions causing trees to sway) will generally require lower sensitivity. A more stable environment can support higher sensitivity.
- Purpose: If the goal is to detect any and all motion, even minor, a higher sensitivity is appropriate. If the goal is to only detect significant intrusions, a lower sensitivity is better.
- Camera Placement: A camera pointed at a busy street will likely need lower sensitivity than a camera pointed at a secluded backyard.
Setting Motion Detection Regions
Many DMSS systems also allow you to define specific regions within the camera's field of view for motion detection. This means you can exclude areas that commonly trigger false alarms (e.g., a road with passing cars) and only monitor areas of interest (e.g., a doorway). The default setting usually uses the entire video image as the effective area for motion detection.
Example Scenario
Imagine you have a camera monitoring your front porch.
- High Sensitivity (e.g., 80-100): A spider crawling across the camera lens, a leaf falling from a tree, or a distant car's headlights might trigger an alarm.
- Low Sensitivity (e.g., 0-20): Only a person walking onto the porch or a package being delivered will likely trigger an alarm.
