| 摘要 |
<p> Fiducial mark patterns (72, 74, 120) for graphical bar codes (10) (i.e., images that contain inconspicuous graphical modulations that encode embedded information (22)) that are characterized by high detection robustness and good local deformation tracking are described. In one bar coding method, a base image (26) is modulated with a graphical encoding of a message (24) to prioduce a graphical bar code (10), and a fiducial mark pattern (72, 74, 120) comprising a plurality of dots arranged to track one or more reference locations and local deformation across the graphical bar code (10) is generated. In another bar coding method, fiducial mark candidates are identified in a fiducial mark pattern (72, 74, 120), a fiducial mark path is computed based upon one or more of the identified fiducial mark candidates, and one or more reference locations are identified based upon the computed fiducial mark path.</p> |
