Digital watermarking algorithm based on Chinese PDF documents
Guan Wei · Jisuanji gongcheng yu sheji · 2007
With the appearance of the problems in the truthfulness, completeness and copyright protection of documents, a digital watermarking algorithm specially towards Chinese PDF documents is put forward by analyzing the working mechanism of PDF and PostScript. The watermarking information originated from the features of the PDF character codes of original documents embeds into the spaces between characters of documents, therefore the protection is realized for the content of documents. According to the results of experiments, the application of the algorithm could offer better anti-modification features to Chinese PDF documents.