The Research And Application Of Cameras Tampering Detection Algorithms

Surveillance cameras are widely used in all aspects of society,as an important means to build a safe and harmonious society.However,the monitoring cameras that have been in natural environments for a long time,would be destroyed by the external environment.For example,captured images exit gray spots,or even are completely blurred if the cameras suffer from dust pollution.And the camera shake,which is caused by strong wind,would lead to video jitter.Therefore,camera tampering detection has become significant in intelligent surveillance system today.In order to solve the automatic detection of the camera tampering,this thesis focuses on the jitter tampering detection and dust tampering detection,and presents the following research work:First of all,the study meaning of the camera tampering detection is introduced in this thesis.Moreover,the research status of the camera jitter tampering detection and dust tampering detection,are described in great detail,which provides a reference and research foundation for the next work.Next,to tackle jitter tampering detection,the longest path based algorithm for extent estimation of jitter was proposed in this thesis.First,global motion estimation is conducted by gray projection algorithm introduced local consistency of jitter.Then,ratio,frequency and amplitude of jitter are calculated according to the longest path algorithm combined with global motion parameters.Finally,the extent estimation of jitter is realized via jitter parameters fusion.Experimental results demonstrate the proposed scheme is of validity and accuracy.Then,for dust tampering detection,a new detection algorithm based on saliency detection and machine learning is proposed in this thesis.First,the method extracts color contrast,texture and shape saliency features.Then,dust candidates are obtained using machine learning.Last,a dust particle localization approach is achieved using regional features.The experiments prove that,the proposed approach is of superiority and accuracy.Finally,this thesis summarizes the work,and points out the direction for further research in the future.