The Research Of Image Steganography Based On Human Visual System And JPFG

With the rapid development of computer network and information technology, informationsecurity has received the attention of the countries, and the steganography for securecommunications has become the hot spot. Steganography technique is the main branches ofinformation hiding technology, realizing the hidden information by hiding secret information tothe public in the digital media. Therefore, the steganography has very important researchsignificance and practical value in the protection of information security with personal, business,and even the national. JPEG images are widely used in the transmission network, steganographyalgorithm is developing rapidly based on the format of the image. The steganography method hashuge potential for development based on the human visual characteristics, with its hiddenperformance is good and the characteristics of large embedded information capacity. YASS is anovel steganography algorithm based on JPEG image, which can effectively resist the mainstreamof steganography analysis method.In the paper, I put forward the improvement of the steganalysis algorithm, based on the JPEGimages make full use of human visual characteristics as the carrier of hiding information. Theexperimental results show that the algorithm was improved in the embedding capacity andsecurity. At the same time, YASS algorithm was described in detail, for the defects existing in theYASS steganalysis algorithm, I put forward some related improvement. The main work asfollows:First, according to the luminance feature and texture features, connecting with the imageblock, put forward a kind of image steganography algorithm based on visual features. This methodtakes advantage of the human visual system characteristics, namely the luminance feature andtexture features, image is divided into three areas: strong embedding area, time embedded area andweak embedded area using this feature for each partition, and different bits of the confidentialinformation is embedded in different regions; When the secret information embedding, use thenoise visibility function and planar weighted pixels high to calculate each block of brightness and texture features，determining the area of block, hidden data is non-uniformly embedded in theimage luminance component DCT of low frequency and medium frequency quantizationcoefficients, effectively reducing the visual difference between stego-image and the original image.Finally, the results also confirmed that algorithm can improve the capacity of secret information,the performance of resistance testing, and maintain a higher peak signal to noise ratio.Second, considering that the YASS algorithm against steganography analysis ability isinsufficient, this paper proposes a new improved algorithm YASS. Algorithm is proposed tominimize the embedding distortion calculation method, distortion analysis of the quantized DCTcoefficients embedded block modified, the distortion of minimal impact of AC DCT coefficientsare chose to embed secret information, and replace the traditional method directly by choosing thetop19in the AC DCT coefficients. The experimental results show that, according to the orderfrom small to large, select the embedding distortion embedding channel, the improved algorithmis better than the original steganography method in both security performance and visual quality.