Each alarm has one condition that governs when the alarm state for a given camera is OK and when it is ALARM. Each alarm also can have a series of actions that will be executed when a given cameras state changes to ALARM and the other execution conditions in the general parameters are satisfied.

Right now, there is only one type of condition and one type of action. More are planned in the future, to monitor more aspects of a camera and to provide the option for more automated reactions. For now, the one available condition already enables the detection of a wide range of potential misbehaviours, and the provided action will allow you to more easily stay on top of things.

The following is a list of available conditions and actions, and an explanation of their function and configuration.

Conditions

On Event Alarm Condition

The OnEventAlarmCondition allows you to listen to camera events, and raise an alarm if more than a certain amount of a certain event occur within a certain time.

Event Type: The type of camera event the alarm should listen to. Note that some events won’t make sense for certain types of cameras, since some events are specifically produced by certain peripherals. There is no verification whether the event you selected matches your default peripherals configuration. There’s a bit of help with that further down if you feel unsure.

Severity: What exact severity of the specified event type the alarm should listen to. Usually this will be ERROR. In fact, some events, like the MissingImageEvent or MissingHeartbeatEvent, only occur with severity ERROR.

Events in Period: The alarm is raised if a camera produces this many or more events of the selected type and the selected severity within a certain period of time.

Period length: The length of the measuring period in seconds. If a camera produces as many or more of the configured events as is set in “Events in Period” within this many seconds, the alarm will be raised. Note that the period does not refer to a fixed time window. At each evaluation (usually every minute), the condition will evaluate all camera events that occurred during the last <Period Length> seconds.

Typical events and how to use them

Actions

Actions determine what happens when an alarm is raised for a camera. Certain actions have the added benefit of allowing extending their configuration on a per-camera basis, without altering the base configuration of the alarm. This means that these actions can also be extended by power users, so that some of your end customers can influence additional behavior. This is especially important for notifications, where customers can add additional email addresses to receive alarm notifications for their cameras themselves, and define custom messages specifically tailored to the camera and alarm.

Notify By email

This action sends an email to a configurable list of recipients when an alarm is raised. It is also possible to configure the content of the mail.

Email subject: The subject of the email being sent. Note that for the base alarm configuration, this is best left blank. When blank, a subject containing the ID of the camera that raised the alarm will be generated. Since the base configuration is not on a per-camera basis, entering a custom subject means that the camera that raised the alarm is not identifiable in the subject.

Email title: The header printed into the emails body.

Email message: The main message contained in the emails body. Again, for the base configuration it may be best to leave this blank. If blank, a default message will be generated based on the condition of the alarm, and containing the ID of the camera. Changing the message in a camera specific extension, however, can offer the opportunity to write less technical messages for your customers, or using a different language.

If you override both the subject and the message in the base configuration of the alarm, the email will contain no information about what camera is actually affected!

Notification Recipients: A list of email addresses that are to receive the notification. Note that all email addresses configured in the base alarm configuration will receive the email as configured in that configuration. Extending the action for a camera does not influence the content received by the email addresses configured in the alarm itself. Even if somebody were to add an email address in an extension that is already contained in the alarm configuration, that email address will only receive the notification as defined by the alarm configuration. This is to ensure that no lower level user can indirectly tamper with things they have no permission for.