Method and a device for detecting a watermark in digital data

A device for detecting watermarks in digital data for the purpose of electronic copyright management system comprising:

• means for transforming the original, unwatermarked data,
• means for tagging the resultant components of the transformed data,
• means for selecting significant tagged components in the said transformed data,
• means for transforming the suspected watermarked data,
• means for tagging the components in the transformed suspected watermark data,
• means for selecting the tagged components from the transformed suspected watermarked data corresponding to those selected as significant in the original transformed data, and
• means for comparing said two groups of selected tagged components to detect the presence of watermarks.

A computer program product comprising computer readable program code stored on a computer readable storage medium embodied therein for detecting watermarks in digital data for the purpose of electronic copyright management system, comprising:

• computer readable program code configured for transforming the original, unwatermarked data,
• computer readable program code configured for tagging the resultant components of the transformed data,
• computer readable program code configured for selecting significant tagged components in the said transformed data,
• computer readable program code configured for transforming the suspected watermarked data,
• computer readable program code configured for tagging the components in the transformed suspected watermark data,
• computer readable program code configured for selecting the tagged components from the transformed suspected watermarked data corresponding to those selected as significant in the original transformed data, and
• computer readable program code configured for comparing said two groups of selected tagged components to detect the watermarks.