期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2002
卷号：XXXIV Part 2
页码：651-656
出版社：Copernicus Publications
摘要：A digital image can be watermarked for security purposes by taking a coded digital record and embedding it to the digital image in such a manner that it cannot be easily detected or r emoved. The record that becomes the watermark is often a r ecognizable logo. Using variable parameters entered by the user, the logo is mixed using a watermark algorithm until it appears as no more than random black spots. These spots can be inserted into the digital image as background noise, and just as easily removed if the input parameters are known. If the watermark is removed and the logo is not intact, then it suggests that the digital image has been altered from its original state. Digital images have been routinely used in such areas as remote sensing, backdrops to CAD drawings, and medical imaging. The digital image is often of consider able value or contains information that is cr ucial for a particular application. Therefore, ensuring its authenticity and ownership is of considerable importance
