Cisco 8620, Справочное руководство

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Cisco Video Surveillance 8620/8630 IP Camera Reference Guide
Chapter 5 Configuration
Applications > Tampering detection
Set up the event source as DI on Event > Event settings Add Event > Trigger. See the “Event > Event
settings” section on page 5-36 for detailed information.
Applications > Tampering detection
This section explains how to set up camera tamper detection. With tamper detection, the camera is
capable of detecting incidents such as redirection, blocking or defocusing, or even spray paint.
To set up the camera tamper detection function, follow these steps:
Step 1 Click to select the check box before tampering conditions: Tampering detection, Image too dark
detection, Image too bright detection, or Image too blurry detection, then enter the tamper trigger
duration (10 sec. ~ 10 min.)). The duration specifies the set of time before the tampering is considered
as a real alarm. This helps avoid false alarms by short-lived ch.
The tamper alarm will be triggered only when the tampering factor (the difference between current frame
and pre-saved background) exceeds the trigger threshold. Conditions such as image too dark, too bright,
or too blurry (defocused) can also be configured as tampering conditions. The Trigger threshold
determines how sensitive your is tamper detection setting.
• Too bright—Shining a flashlight. The average lighting level of the scene is taken into consideration.
•
Too dark—Covering the objective or spraying paint.
• Too blurry—Blurry scene can be the result of strong interference on the device, such as EMI
interference.
Step 2
You can configure Tampering Detection as a trigger element to the proactive event configurations in
Event > Event settings > Trigger.
For example, when the camera is tampered with, the camera can be configured to send the pre- and
post-event video clips to a networked storage device. See the
“Event > Event settings” section on
page 5-36 for detailed information.
Applications > Audio detection
Audio detection, along with video motion detection, is applicable in the following scenarios:
•
Detection of activities not covered by camera view, for example, a loud input by gun shots or
breaking a door/window.
• A usually noisy environment, such as a factory, suddenly becomes quiet due to a breakdown of
machines.
•
A PTZ camera can be directed to turn to a preset point by the occurrence of audio events.
• Dark environments where video motion detection may not function well.
In the example shown in Figure 5-9 , the red circles indicate where the audio alarms can be triggered
when breaching or falling below the preset threshold.