A Typology of CV Markers opencv calibration checker pattern for homography reactivision corner detection for calibration dot tracking markers bar codes qr codes custom qr codes Microsoft tags fiducial markers AR tracking marker for After Effects ARTag markers
Nice collection - but don't forget the ever-popular Microsoft Surface tags! I only mention these because I just had to use them :-/
Byte tags: http://msdn.microsoft.com/en-us/library/ee804885(v=surface.10).aspx
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