Local and global integration of discrete vector fields
Several methods in the field of shape reconstruction [6, 8, 11] (most shading based methods) lead to gradient data that still have to be transformed into (scaled) height or depth maps, or into surface data for many applications. Thus the reconstruction accuracy also depends upon the performance of such a transformation module. Surprisingly, not much work was done so far in this area. This paper starts with a review of the state of the art and discusses two approaches in detail. Several experimental evaluations of both methods for transforming gradient data into height data are reported. The studied (synthetic and real) object classes are curved and polyhedral objects. General qualitative evaluations of the compared transformation procedures are possible in relation to these object classes and in relation to different types of noise simulated for synthetic objects.
KeywordsGradient Field Fourier Expansion Integration Technique Height Data Surface Integration
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- Bichsel, M.: Fast Photometric Stereo: Regularization vs. Wiener Filtering. IAPRS, Vol. 30, Part 5W1, ISPRS Intercommission Workshop “From Pixels to Sequences”, Zurich, Mar. 22–24, 1995, 245–252.Google Scholar
- Coleman, N.E., Jr., Jain, R.: Obtaining 3-dimensional shape of textured and specular surfaces using four-source photometry. CGIP 18, 309–328 (1982).Google Scholar
- Healey, G., Jain, R.: Depth recovery from surface normals. ICPR’84, Montreal, Canada, Jul. 30-Aug. 2, 1984, 894–896.Google Scholar
- Horn, B.K.P.: Height and gradient from shading. Int. J. of CV 5, 37–75 (1990).Google Scholar
- Horn, B.K.P., Brooks, M.J.: The variational approach to shape from shading. CVGIP 33, 174–208 (1986).Google Scholar
- Klette, R., Koschan, A., Schlüns, K.: Computer Vision - Räumliche Information aus digitalen Bildern. Braunschweig: Vieweg 1996.Google Scholar
- Klette, R., Schlüns, K.: Height data from gradient fields, Proc. Machine Vision Applications, Architectures, and Systems Integration V, SPIE 2908, Boston, Massachusetts, Nov. 18–19, 1996, 204–215.Google Scholar
- Rodehorst, V.: Vertiefende Analyse eines Gestalts-Constraints von Aloimonos und Shulman“. Technischer Bericht, CV-Bericht 8, Institut für Technische Informatik, TU Berlin, 1993.Google Scholar
- [Il]Woodham, R.J.: Photometric method for determining surface orientations from multiple images. Optical Engineering 19, 139–144 (1980).Google Scholar
- Wu, Z., Li, L.: A line-integration based method for depth recovery from surface normals. CVGIP 43, 53–66 (1988).Google Scholar