In this paper a new method for detection of camera tampering is proposed. Some examples for camera tampering are: shaking the camera, movement of the camera, occlusion, and rotation of the camera. The tampering may be intentional or unintentional. In the proposed algorithm, in addition to detection of the exact nature of tampering, the exact amount of tampering also can be detected (i.e. the amount and direction of movement). This will help operator in diction making for management in surveillance system. The proposed algorithm detect the shaking using current and previous frames, as well as by constructing a total background based on all frames and building a temporary background based on last 10 frames. The proposed method employs the SURF feature detector to find interest points in both of two backgrounds and compare and match them using MSAC algorithm. The transformation matrix can be obtained to detect the camera movement, camera image zoom and camera rotate. Finally, using the method sobel edge detection the camera occlusion and defocus can be detected. The method also detect the sudden shut downs in camera or images loss. Another features of the algorithm is providing the information concerning the camera tampering.

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