摘要

In order to reduce the influence on cover image caused by embedding algorithm, while keeping the histogram characteristics of cover image, in this paper a histogram preserving steganography algorithm is proposed based on dividing a secret message into blocks. The secret message and cover image are divided into blocks and the hamming distance of least significant bits is calculated, and then secret message block and mark-bit of cover image block are processed according to the hamming distance. In terms of histogram profit-lost compensation, the processed secret message block is then embedded into the cover image block. Theoretical derivation of modification gain and embedding efficiency in the algorithm is well verified by tests. Compared with the matrix coding steganography algorithm, which also has less unwanted effect on the cover image, the steganography algorithm proposed in this paper achieves higher embedding efficiency, higher capacity, and lower computational complexity other than high histogram consistency. A tradeoff control between embedding capacity and image distortion can be flexibly manipulated at nearly no or little cost of compromising the histogram characteristics.

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