Research On Digital Watermarking Algorithm For Tile Remote Sensing Image Based On QR Code

Remote sensing image data,which is a kind of basic and strategic national information resource, plays a significant role in the earth science research and infrastructure construction. With the advent of the Internet era, network geographic information service platform, which is symbolized by Google Earth or Map World,presents a novel prospect for the network application of remote sensing image data,greatly improve the sharing and usage of remote sensing image data.Due to mass data characteristics of the remote sensing image data, remote sensing image data is generally used in the form of tile data for storage, management,and application by network geographic information service platform. Tile remote sensing image data is characterized by mass production, rich resources, easy to use and download. However, these benefits can lead to different kinds of security issues,such as infringement, information leak,illegal usage and profit. In order to safeguard the legitimate rights and interests of the data producers and crack down on all illegal infringement behaviors, scientific and effective technical measures should be introduced to strengthen the safety management of tile remote sensing image data.As a frontier in the field of information security technology, digital watermarking technology provides a feasible technical method for tile remote sensing images protection. Digital watermarking technology, which is different from the traditional encryption technology, embedded secret watermarking into target data, and makes them intergrated tightly. Digital watermarking technology, which is used for copyright protection, content authentication, tracking infringement behaviors and data source, and so on, can effectively solve the information security problems of tile remote sensing image data.A suitable watermarking generation method should be selected based on the data features of tile remote sesing images in the research of digital watermarking technology. QR code, which is characterized by high information capacity, strong corrected ability and convenient usage,can coordinate with the data features of tile remote sensing image data. QR code, used as watermarking, which can effectively improve the imperceptibility and robustness of watermarking algorithm for tile remote sensing images.This article, which combines the QR code technology and digital watermarking technology, focuses on the research of digital watermarking algorithms for tile remote sensing images. The main research work and achievements are as follows:(1) Based on the data features of tile remote sensing image data, technical requirements of digital watermarking algorithms are put forward. Watermarking attack methods and applications of digital watermarking technology towards tile remote sensing images have also been proposed.(2) Based on watermarking security requirements, this paper proposes a QR codes image scrambling method which combines scrambling degree optimization and Arnold transform,which can improve the security of the watermarking. On the basis of the watermarking capacity of tile remote sensing images, this paper puts forward a data compression method of QR code image, reducing the data size of embedded watermarking. This method does not change the result of QR code identify.(3) According to the low robustness of the traditional LSB watermarking algorithm,this paper proposes a improved algorithm. Error correction coding mechanism is used for watermarking embedding and detection, which improves the accuracy of watermarking detection and enhances the robustness of the normal image processing attack. According to the watermarking desynchronization problems caused by geometrical distortion, a tile remote sensing image watermarking algorithm based on quantitative pixel values, spread spectrum modulation and interval division, has been proposed.By converting the image pixel values into interval value which is more stable towards geometrical distortion, the synchronous relationship between the watermarking embedding locations and watermarking bits could be identified. As a result, this algorithm can effectively resist geometrical distortion.(4) According to the splicing processing characteristics of tile remote sensing images, this paper proposes a algorithm based on positioning block mechanism and DCT. By constructing positioning block, the problem of locating the tile remote sensing image which has been embedded watermarking is solved. In the process of watermarking embedding, the improved quantitative mechanism is adopted to embed watermarking in the DC components of DCT frequency domain, in order to meet the requirements of the resistance of JPEG compression attack. At the same time, the index mechanism and error control are introduced in order to improve the security and fidelity of this algorithm.(5) Based on analyzing the advantage of tile remote sensing images watermarking algorithm using DWT, a algorithm with composite attack resistance,which combines DWT and DCT, is put forward in this paper. In the process of watermark embedding, the matrix-coding scheme is used, which can improve the efficiency of the watermarking embedding, further enhance the ability of resistance JPEG compression attack. At the same time, the imperceptibility and robustness of the algorithm have been balanced.