Research Of Algorithms In Image Information Hiding And Steganalysis

There are the two important branchs in the field of information hiding technology, which is information Hiding or Steganography and steganalysis.Information hiding will embed secret information in the cover files and form the stego files, in order to protect the cover files or hide secret information. The cover files can be digital text, digital images, digital audio and digital multimedia.On the other hand, steganalysis will detect whether to hide secret information or not, what is the amount of the secret information, as well as how to recover the secret information. The detection of hidden information is the main purpose of the steganalysis. It is an important means to prevent illegal dissemination of information, but also is the measure to evaluate the information hiding algorithm security.Information hiding of the digital images has become a hot spot of the field of information security. The information hiding algorithm and information hiding analysis algorithms of digital images are proposed on the basis of the understanding forefront of research of information hiding, in-depth analysis of the essence and the latest research results of information hiding and the statistical nature of the digital images. The main research results are as followed:1. Information hiding algorithmsIn the spatial domain, through the analysis of the correlation of images bit-level and the relation of adjacent pixels level, it is proposed which is an asymmetric LSB information hiding algorithm of resisting SPA(ALRS method). The analysis and experimental results show that ALRS can effectively resist the SPA analysis and is more than similar information hiding algorithm in the accuracy, flexibility and computational efficiency.In the frequency domain, through the analysis of correlation of adjacent pixels level, the distribution characteristics of frequency domain coefficients, as well as the defect of the YASS algorithm, it is presented by RASA algorithm. In the RASA algorithm, the size of the parent block will change with the key. Experimental results show that the security of the RASA algorithm has been improved greatly.2. Steganalysis algorithmsBy analyzing the distribution of image features and correlation of size of image and its frequency domain coefficients, it is designed by a steganalysis of information hiding For F5(FSF algorithm) combining with F5hidden features of the algorithm,. The experimental results show that the performance of FSF algorithm is more stable and higher accuracy.Based on the correlation of size of image and its frequency domain coefficients, it is proposd by a method of calculating primary quantization matrix of JPEG(CM algorithm). The approximation of the original image in the CM algorithm can be get more stable than others. The experimental results show that the CM algorithm is more effective algorithm.