Summary: | 碩士 === 靜宜大學 === 資訊管理學系 === 104 === The Internet has become a popular public communication channel to transmit digital media. However, digital media can be easily duplicated and tampered by illegal users and that is why integrity protect of the digital media becomes more and more important. In order to solve this problem, the data hiding schemes that use digital medium as cover medium had been proposed. The secret data is then embedded into the cover medium to generate the stego-medium. The stego-medium is imperceptibility and it can avoid the assaulter notice and prevent attack. The data hiding schemes can be divided into two main categories: irreversible data hiding schemes and the reversible data hiding schemes. Reversible data hiding schemes have the characteristic of recovery to original media after the secret data was extracted.
In this thesis, we proposed two data hiding schemes. The first scheme is adapts to BTC and difference expansion. We consider the compressed codes of BTC to be the pairs of pixels in difference expansion. At the remaining part of this scheme, we discuss the possibility of embedding the location map in bit maps, and the experimental result shows it is possible. The second scheme is adapts to histogram shifting. In order to choose multi pairs of pick and zero point to embed secret data, we modify the histogram of pixels. After modification, the histogram of pixels can find multi pairs of pick and zero point to embed.
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