Dynamic digital watermark

Abstract

Some implementations may include a computer-implemented method for applying at least two digital watermarks to a digital document, the method including: receiving a digital document comprising visual contents; generating a first digital watermark to be visually presented at a first time point; generating a second digital watermark to be visually presented at a second time point, the second digital watermark being different from the first digital watermark and the second time point being different from the first time point; and applying both the first digital watermark and second digital watermark to the digital document t.

What is claimed is: 
     
         1 . A computer-implemented method for applying at least two digital watermarks to a digital document, the method comprising:
 receiving a digital document comprising visual contents;   generating a first digital watermark to be visually presented at a first time point;   generating a second digital watermark to be visually presented at a second time point, the second digital watermark being different from the first digital watermark and the second time point being different from the first time point; and   applying both the first digital watermark and second digital watermark to the digital document.