Computing the Length of the Video Archive

Enhancing Video for Security

camera at close range and blinding the camera is not considered sabotage unless that person remains in front of the camera for more than 48 seconds.

Event log

To search the event log, use an Event session. See Event Session: to Search the Log of Events, p. 193.

Moved-type CSD: Learning and Rearming Alarms

Good Image

A "Good Image" is reported, to the left of Reset, when a scene has enough features for the unit to detect if someone or something has moved the camera, and sabotage can be inferred. A "Bad Image" is reported when the image is indistinct, for example, if the camera is pointed at a wall of uniform color.

From Learning to Running

When Moved is selected, or its threshold changed, the Multi-Media unit "learns about" the scene shown by the camera; "Learning" is reported, to the left of Moved, for 2 minutes to a maximum of 3 minutes. Do not blind or blur a camera while "Learning" is displayed. When learning ends, "Running" is displayed to the left of Moved.

Resetting learning

Reset is enabled when Moved is selected. Clicking Reset starts Learning again, and should be used whenever the camera is moved intentionally to show another scene, or if the scene's lighting or content changes dramatically. Reset has no effect on Blind and Blur.

Rows of mobile objects

Moved is sensitive to large scale changes in a scene. For example, using Moved for a camera that shows many chairs in a row, close by, such as in an airport or casino, may not be effective. Clicking Reset while people are sitting makes the unit "learn" that sitting persons are not to be considered as sabotage. When the chairs empty, the scene may have changed enough for the unit to trigger a log entry or an alarm. And if the operator makes the unit "learn" when the chairs are empty, then CSD may be triggered when people sit in the chairs. The same can be said for a row of vehicles that are frequently moved, such as in a taxi stand or truck depot.

Alarms

After rearming an alarm produced by the Moved-type sabotage detection, move the camera back to the scene that you need to monitor, and click Reset.