Real-time structured light coding for adaptive patterns

• Published in: Journal of real-time image processing Vol. 8; no. 2; pp. 169 - 178
• Main Authors: Maurice, Xavier, Graebling, Pierre, Doignon, Christophe
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-06-2013; Springer; Springer Nature B.V
• Subjects: Algorithmics. Computability. Computer arithmetics; Algorithms; Applied sciences; Artificial intelligence; Behavior; Closed loops; Coding; Computer Graphics; Computer Science; Computer science; control theory; systems; Exact sciences and technology; Field of view; Geometry; Image Processing and Computer Vision; Multimedia Information Systems; Neighborhoods; Original Research Paper; Pattern Recognition; Pattern recognition. Digital image processing. Computational geometry; Pseudorandom; Real time; Reconstruction; Robustness; Signal,Image and Speech Processing; Structured light patterns; Theoretical computing; Structured light; Pattern coding; Pseudo-random arrays; Perfect maps; Real time; Occlusion; Pipeline processor; Image processing; Epipolar geometry; Adaptive method; Image reconstruction; Codebook; Minimal distance; Robustness; Content analysis; Closed loop; Computer vision; Hamming distance; Probabilistic approach; Texturation; Visual field; String matching; Correspondence principle; Tridimensional image; Curvature; Occultation; Pattern matching
• ISSN: 1861-8200; 1861-8219
• DOI: 10.1007/s11554-011-0200-2

Coded structured light is a technique that allows the 3D reconstruction of poorly or non-textured scene areas. With the codes uniquely associated with visual primitives of the projected pattern, the correspondence problem is quickly solved by means of local information only, with robustness against disturbances like high surface curvatures, partial occlusions, out-of-field of view or out-of-focus. Real-time 3D reconstruction with one shot is possible with pseudo-random arrays, where the encoding is done in a single pattern using spatial neighbourhood. To correct more mismatched visual primitives and to get patterns globally more robust, a higher Hamming distance between all the used codewords should be suited. Recent works in the structured light field have shown a growing interest for adaptive patterns. These can account for geometrical or spectral specificities of the scene to provide better features matching and reconstructions. Up till today, such patterns cannot benefit from the robustness offered by spatial neighbourhood coding with a minimal Hamming distance constraint, because the existing algorithms for such a class of coding are designed with an offline coding only. In this article, we show that due to two new contributions, a mixed exploration/exploitation search behaviour and a
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