High-Payload Image Steganography Using k-Way Block Matching

• Main Authors: Yeh-Shun Chen, 陳耶舜
• Other Authors: Ran-Zan Wang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/hqwtw8

碩士 === 銘傳大學 === 資訊傳播工程學系碩士班 === 94 === Image hiding is the technique that embeds important image invisibly in a cover image, it can be used to protect important image against illegal access. In this thesis, we propose two high-payload image steganographic methods, a two-way block matching method and an k-way block matching method. In the first method, the important image is first divided into many non-overlapping blocks of the same size. For each block, a block-matching procedure is applied to search for the best-similar block from a series of candidate blocks. The obtained indices are then recorded in the LSB of the cover image using a hop-embedding scheme. In the second method, we extend the block matching procedure to an multi-level searching scheme, in which the sizes of blocks in each searching level are different. Experimental results show that the qualities of both the stego-images and the extracted important images obtained in the proposed methods are high, which shows the feasibility of the proposed method in protecting important images.