Research And Implementation Of The Traceability System Of Mobile Phone Screen Shot

On the client side of secret-related e-government applications,cell phone screen leaks often occur.Therefore,it is of practical significance to trace the source of the leak to the source of the leak through the screen shot and deter the leak of the screen shot.The user client information(such as IP address,user code,etc.)is steganographically generated to generate an image watermark that can be embedded in the background of the client.When a leak occurs,the leaker can be held accountable by restoring the steganographic information.However,the image watermark information is easily damaged due to the camera angle,illumination,moiré and other influences during the screen shooting process,which brings great challenges to traceability.At present,in the domestic and foreign research literature on steganographic watermarking,there are few references to discuss the steganographic traceability of mobile phone screen shots.This thesis conducts exploratory research based on the actual needs of users in the project,and proposes a generation and extraction of screen image steganographic watermarks,to realize the traceability system of mobile phone screen capture,the main research contents are as follows:(1)Design an image watermark generation method based on shading.Aiming at the visual quality of the Web page after embedding the image watermark,the concealment of the image watermark in the Web page,and the reducibility of the steganographic watermark when the screen is leaked,the R channel and G channel of a single pixel image are used to generate shading,The B channel pixel steganographic watermark information generates image watermarks that can be embedded in web pages.Aiming at the problem of missing watermark caused by illumination and moirédistortion,the repeated steganographic watermark method is used to increase the number of candidate pixels that can be used for steganographic watermark restoration.(2)Design a watermark extraction method for mobile phone screen images.For perspective and color distortion problems,use image preprocessing to correct images and enhance image color.Aiming at the problem of blind watermark extraction and inaccurate positioning caused by rotation,scaling and translation in lens distortion,an automatic watermark positioning method is proposed to locate all complete watermark image blocks and extract all complete watermark information sequences.Aiming at the problem of local watermark information errors in distorted images,a block reorganization compensation method is proposed to reorganize all complete watermark information sequences into blocks to improve the accuracy of watermark extraction in screen shot distorted images.(3)Design and implement the traceability system of mobile phone screen shot.The system’s shading-based image watermark generation method provides embedded image watermark services for e-government platforms that request the steganography service,such as the cadre information reporting system.When a screen leak occurs,the system uses the watermark extraction method of the screen shot of the mobile phone to extract the steganographic information of the watermark and trace the source to the source of the leak.