Abstract :
Moire fringe topography and rasterstereography are 3-D optical imaging techniques, which provide height and curvature maps of the subject or the object under study. These are non-contact and non-invasive techniques, which project moire and raster grids on the body. The distorted grids contain height and curvature information, which may be recovered using image-processing algorithms. These technique are being applied to face recognition. The information may be stored in the database and not easily accessible to ordinary citizen. Hence, the chances of fake pictures or fabricated patterns are minimized. Techniques are developed to project, simultaneously, moire and raster grids and analyze height and curvature information, separately, using selective optical filtering, which could be used to record height and curvature patterns during a certain action, e. g., uttering a standard word. Edge-based algorithms, combined with moire contours and raster patterns, allow study of face movements through changing height and curvature maps. A multiple-level screening of suspects using these technologies is proposed.
Keywords :
edge detection; face recognition; filtering theory; moire fringes; stereo image processing; 3D optical imaging techniques; curvature maps; curvature patterns; distorted grids; edge-based algorithms; face recognition; height patterns; image-processing algo-rithms; moire contours; moire fringe topography; noncontact techniques; noninvasive techniques; pattern recognition; raster grids; raster patterns; raster stereography; selective optical filtering; Face recognition; Image databases; Information analysis; Optical distortion; Optical filters; Optical imaging; Optical recording; Pattern analysis; Pattern recognition; Surfaces; Face recognition; image processing; stereophotography;