| 摘要 |
<p>Meta-information, such as a digital watermark, that is associated with a document is encoded by using characters, or sequences of characters, that are 'invisible' when rendered. Characters such as spaces, tabs, carriage returns, backspaces, line feeds, and so on are used to encode the watermark. The encoded 'invisible' meta-information item is preferably appended to the document. A receiving device that is compatible with this encoding is able to decode and process the meta-information, for example, to verify the contents and/or the originator of the document. A receiving device that is not compatible with this encoding will merely display or print additional 'white space' corresponding to the 'invisible' meta-information. By appending this invisible encoding to the document, this additional white space will occur after the display or printing of the document, in a visually unobtrusive form.</p> |
