Embedded message extraction for visible watermarking

摘要: A watermarking system uses distinct bit patterns to identify a logic 0, 1, and marker bit, which demarcates segments of information. Marker bits, are printed on both foreground background areas an image, outline message blocks. In extraction, preprocessing step removes any white boarders, identifies the best defined corner block, crops rotates image place identified at top-left corner. Message extraction scans rotated in window increasing size during multiple cycles. During each cycle, if pattern cannot be as data then examined area is increased rechecked see it specifically bit. If no information can definitively identified, assigned value based 50% random assignment.