Watermarking for Authentication of LZ-77 Compressed Documents
Fragile Watermarking by exploiting the multiplicity of encoding of a file using LZ77- based compressed method (we called“LZS-77”), has been proposed recently as a new method of document authentication. It allows one to hide enough information within the compressed document to warrant its authenticity. However, the watermark embedding will degrade the compression performance. In this paper, some variations have been made to the LZS-77 algorithm to reduce the compression degradation. The experimental results show that our algorithm (we called“LZSC-77”), compared to the LZS-77 algorithm, can improve compression rates on many files of the Cargary corpus and Canterbury corpus.
KeywordsLZ77 algorithm document authentication fragile watermark
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