| 摘要 |
A scheme for inserting and extracting an invisible fragile watermark in a image/video sequence, in order to verify whether a watermarked image has been tampered with. According to one aspect of the invention, there is provided a method of watermarking a digital image, comprising: obtaining digital image coefficients; forming a plurality of arrays of image coefficients, each array comprising a predetermined number of image coefficients; selecting a plurality of input values, selected input values each representing binary 0s or 1s; and for each array: determining a binary value as a watermark component bit; calculating a numerical value being representative of the image coefficients; and, if necessary, modifying one or more of the image coefficients, such that the representative numerical value becomes equal to a selected input value which represents the determined watermark component bit. According to other aspects of the invention, there are provided a corresponding method of detecting a watermark, and corresponding hardware and software devices. |
