Two Different Vector-based Information Hiding Method

With the coming of the information era and the widespread applications of internet technology, the information security is going to be an important issue. An emerging information security technology, information hiding, comes out for it and has attracted more and more research interest as an effective scheme for the covered communication and for copyrights protection. Two types of the information hiding are studied in this thesis. One is based on image and the other on DNA.Firstly, this thesis introduces a human-visual-system (HVS) based JPEG data hiding scheme. Here, a HVS-based quantization table is modified at first, and used to quantize the DCT coefficients of the original cover image. At last, the information to be hidden is embedded into the quantized DCT coefficients to generate the stego image. The simulation results show that, comparing with the well-known QTM scheme, the proposed method could achieve higher quality of the stego image while having the same embedding capacity.Secondly, the quantization table of an existing JPEG data hiding scheme based upon Fibonacci matrix, (Fibonacci scheme), is corrected. This scheme is also implemented with the corrected quantization table. To further improve the quality of the stego image, this thesis has also designed a JPEG data hiding method by using the modified Fibonacci p-codes matrix. Experiment results reveal that its embedding capacity is same as the one of Fibonacci scheme, while the quality of its stego image is improved.Meanwhile, this thesis also studies the information hiding methods which use DNA as the covers, and designs a method based upon live DNA. This method realizes to embed the information into the coding part of live DNA by using codon redundancy and arithmetic coding. It will not change the final amino acid sequence, not lead to genetic mutation. Hence, it can be used to protect the findings of the genes and the intellectual properties of gene therapy effectively.In the end of this dissertation, summary of pervious work and suggestions for future work are given.