| 摘要 |
FIELD: physics, computer engineering. ^ SUBSTANCE: invention is related to watermark detection in information signal. Watermark detector (100) is suggested, which detects availability of watermark in information signal. Information signal is correlated with expected watermark (Wi) for every out of multiple relative positions of information signal in respect to watermark, in order to obtain set of correlation results (64). Part of correlation results (64) is mutually correlated (82) with information (81) on shape of correlation peak expected in results. Result of mutual correlation (84) is compared to threshold value in unit (85) of peak detection. Threshold value used in this comparison (85) is established by adapted method in compliance with expected shape. Information (81) on expected shape of correlation peak may be based on knowledge of processing operations, which were undergone or have to be undergone by information signal, or on the basis of shape from previous results of correlation. ^ EFFECT: improvement of accuracy of watermark availability detection in information signal. ^ 21 cl, 10 dwg |
