| 摘要 |
A method of embedding data such as a watermark in a two dimensional information signal such as an image. The method comprises filtering a portion of the information signal using a two dimensional filter. In order to reduce the visibility of the watermark in sharp and elongated edges, the filter is configured to apply a net weighting of approximately zero to the portion of the information signal in at least two non parallel directions. Preferably, the two directions are mutually orthogonal, e.g. horizontal and vertical. The thus filtered signal is used to locally control the watermark embedding depth (energy). |
