Reliability determination of camera fault detection tests

Abstract

There is provided a method for determining the reliability of a fault detection of a camera in a camera system. According to the method data relating to environmental conditions are received (204) and compared to accessed (202) criteria relating to environmental conditions external to the camera and affecting the reliability of the fault detection test. If the received data complies with the criteria it is determined (206) that the fault detection test gives a reliable result. This is advantageous in that false fault detection tests may be identified.

Description

TECHNICAL FIELD[0001]The present invention relates to the field of fault detection of cameras. In particular it relates to a method for determining the reliability of a fault detection of a camera in a camera systemBACKGROUND[0002]Cameras are commonly used for monitoring purposes. For example, cameras may be arranged to monitor premises or vehicles. As the cameras degrade or get out of order, maintenance staff is sent out to repair or replace the cameras. Typically, a monitoring camera is arranged at a remote location and it is therefore costly to send out maintenance staff to perform service work on the cameras.[0003]In order to mitigate this problem, the cameras may perform self-tests such that the cameras themselves may detect if there is a fault which needs to be attended to. If a camera detects that there is fault, maintenance staff may be notified and can take necessary action to repair or replace the camera.[0004]There are different ways of performing self-tests. US2007126869...

AI Technical Summary

Benefits of technology

This patent describes a method of checking the data relating to the environmental conditions of a camera system at a specific time point. The camera system only performs the fault detection test if there is a fault indicated by the test. The method helps avoid false fault detections, which can lead to unnecessary maintenance visits. The camera system also sends the result of the test together with information on its reliability to an external receiver, which enables maintenance staff to decide not to attend to false detections. The method helps improve the reliability of the camera system and reduces downtime for maintenance.

Problems solved by technology

However, in case of a cloudy sky, the pictures would not look as expected.

Then there might be rain drops on the camera housing rendering the picture taken useless for comparison.

Water puddles might also cause a lot of reflections so that the picture cannot be taken into account.

Accordingly, external environmental conditions, such as fog, motion or darkness, may affect the result of a fault detection test.

In particular, a fault detection test only gives a reliable result if the environmental conditions external to the camera complies with certain criteria.

Thus, a test of the IR functionality only gives a reliable result if it is dark.

Thus, a test pertaining to deciding whether condensation has started inside the camera only gives a reliable result if it is moist around the camera.

However, also external factors such as fog or motion of the camera may affect the contrast, sharpness and edges in the images.

Thus, a fault test relating to the optical components in the camera only gives a reliable result if there is no fog and / or if the camera is stationary.

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