Skip to main content

Tips & Tricks for Perimeter Protection

By | July 31, 2019

Dahua’s Analytics+ technology introduces the latest innovations in highly accurate perimeter protection. The technology enhances the tripwire and intrusion detection functions by including an object filter, a highly accurate way to distinguish between people and vehicles. Objects that cross a defined line can be categorized as humans or motor vehicles, making incidents easier to search for and allowing the option of setting up alerts for specific types of intrusions. See a video of the object filter here.

To establish the most successful perimeter protection, use these tips and tricks for installation.

Choosing a Suitable Installation Site

The installation site should provide a large visual field in an open space, without drastic changes in lighting conditions. The scene should be free of visual distractions and frequently moving objects. It should not include large obstacles around the target area that can block the view of intruders.

Sites with clearly-defined borders are ideal for installation, such as gated communities, store entrances, garage entrances, railways, and highways. The absence of a physical barrier doesn’t impede one’s ability to protect a defined perimeter, however. Perimeter protection can be used to detect people falling into bodies of water or intruders on rooftops. The object filter can quickly distinguish a car driving on a sidewalk or people walking on a freeway on-ramp.

Selecting the Right Installation Type

The installation type is also essential to successful perimeter protection. Cameras should be installed at a high position perpendicular to the area being monitored. The recommended installation height is greater than 9.8 feet (3 meters) and the maximum height varies with different lenses. The recommended installation angle is 0° ~ 45°.

Consider what the scene will look like at night. If the camera will be capturing vehicle headlights head-on, the drastic change in lighting conditions will negatively impact detection performance. If ambient light is not bright enough, detection accuracy may be impacted.

Using the Right Lens

The recommended lens is one with a focal length that’s wide enough to cover an entire perimeter if possible. If not, you can design using multiple perimeter protection cameras to provide full area coverage. Make sure the lens you choose is within the install distances referenced below.

For fixed lenses, use this reference table:

Lens focal length (mm) 2.8 3.6 6.0 8.0 12 30
Installing distance (m) 6 8 13 17 26 65
Installing distance (ft) 19.7  26.2










For vari-focal lenses, follow these guidelines:

  • When the install distance is between 16-72 feet (5-22 meters) from the target, select a lens with a focal length of 2.7mm~13.5 mm.

Perusing the Latest Products

Dahua’s newest cameras with Analytics+ allow users to select from one of several advanced analytic behaviors besides perimeter protection; you can optionally choose instead to use people counting with loitering detection, heat mapping for population visualization, or facial attributes analysis. Click here to see the full line.

Setting Up Perimeter Protection

Ready to give it a try? Click here for step-by-step instructions on how to set up perimeter protection.

Close Menu