| 摘要 |
A method for testing (500, 600, 700) a presence of a watermark in a scalable video sequence, for detecting tampering of the scalable video sequence, includes receiving (502, 602) a scalable video sequence having a plurality of blocks, wherein a number of blocks include at least one watermark coefficient; performing a discrete cosine transform on said video sequence, thereby recovering a plurality of coefficients associated with one or more block(s); and comparing (506) a number of positive coefficients with a number of negative coefficients to determine whether said received scalable video sequence has been tampered with. A method for classifying a type of watermark attack on a scalable video sequence. This allows a determination to be made as to whether a scalable video sequence has been tampered with; and provides a good estimate as to the type of attack/tampering to the video sequence. |
