process produce outputs that are sufficient for further
biological investigation. Both number of analyzed
specimens and number of obtained z-values for statis-
tical analysis are unprecedented and this approach is
so far the only one successfully used in field. Further
research will be carried out in order to describe the
surface more appropriately for biological purposes.
REFERENCES
Bachmaier, M. and Backes, M. (2008). Variogram or semi-
variogram - explaining the variances in a variogram.
Precision Agriculture.
Bouguet, J.-Y. (2005). Camera calibration toolbox
for matlab. http://www.vision.caltech.edu/bouguetj/-
calib doc/index.html.
Brodie, H. J. (1951). The splash-cup dispersal mechanism
in plants. Canadian Journal of Botany, (29):224–230.
Chaudhuri, S., Rajagopalan, A., and Pentland, A. (1999).
Depth from Defocus: A Real Aperture Imaging Ap-
proach. Springer.
Coleman, Jr., E. and Jain, R. (1981). Shape from shading
for surfaces with texture and specularity. In IJCAI81,
pages 652–657.
Crum, H. (2001). Structural Diversity of Bryophytes, page
379. University of Michigan Herbarium, Ann Arbor.
Darboux, F. and Huang, C. (2003). An simultaneous-
profile laser scanner to measure soil surface microto-
pography. Soil Science Society of America Journal,
(67):92–99.
Heikilla, J. (2000). Geometric camera calibration using cir-
cular control points. IEEE Transactions on Pattern
Analysis and Machine Intelligence 22, (10):1066–
1077.
Heikilla, J. and Silven, O. (1997). A four-step camera cal-
ibration procedure with implicit image correction. In
IEEE Computer Society Conference on Computer Vi-
sion and Pattern Recognition (CVPR97), pages 1106–
1112.
Horn, B. (1986). Robot Vision. MIT Press.
Horn, B. and Brooks, M. (1986). The variantional approach
to shape from shading. In Computer Vision Graphics
and Image Processing, volume 22, pages 174–208.
Howard, I. P. and Rogers, B. J. (1996). Binocular Vision
and Stereopsis, pages 212–230. Oxford Scholarship
Online.
Jarvis, R. A. (1983). A perspective on range finding tech-
niques for computer vision. In IEEE Trans. Pattern
Analysis and Machine Intelligence, volume 5, pages
122–139.
Kanade, T. and Okutomi, M. (1994). A stereo matching
algorithm with an adaptive window: Theory and ex-
periment. IEEE Transactions on Pattern Analysis and
Machine Intelligence, 16(9):920–932.
Kolmogorov, V. and Zabih, R. (2001). Computing vi-
sual correspondence with occlusions using graph cuts.
iccv, 02:508.
Liao, M., Wang, L., Yang, R., and Gong;, M. (2007). Light
fall-off stereo. Computer Vision and Pattern Recogni-
tion, pages 1–8.
Magda, S., Kriegman, D., Zickler, T., and Belhumeur, P.
(2001). Beyond lambert: reconstructing surfaces with
arbitrary brdfs. In ICCV, volume 2, pages 391–398.
Motyka, O., Krumnikl, M., Sojka, E., and Gaura, J. (2008).
New approach in bryophyte canopy analysis: 3d im-
age analysis as a suitable tool for ecological studies of
moss communities? In Environmental changes and
biological assessment IV. Scripta Fac. Rerum Natur.
Univ. Ostraviensis.
Nayar, S. K., Watanabe, M., and Noguchi, M. (1996). Real-
time focus range sensor. IEEE Transactions on Pat-
tern Analysis and Machine Intelligence, 18(12):1186–
1198.
Ogale, A. and Aloimonos, Y. (2005). Shape and the stereo
correspondence problem. International Journal of
Computer Vision, 65(3):147–162.
Ortiz, A. and Oliver, G. (2000). Shape from shading for
multiple albedo images. In ICPR, volume 1, pages
786–789.
Prados, E. and Faugeras, O. (2005). Shape from shading: a
well-posed problem? In Computer Vision and Pattern
Recognition, volume 2, pages 870–877.
Proctor, M. C. F. and Tuba, Z. (2002). Poikilohydry and
homoiohydry: antithesis or spectrum of possibilites?
New Phytologist, (156):327–349.
Rice, S. K., Collins, D., and Anderson, A. M. (2001). Func-
tional significance of variation in bryophyte canopy
structure. American Journal of Botany, (88):1568–
1576.
Rice, S. K., Gutman, C., and Krouglicof, N. (2005). Laser
scanning reveals bryophyte canopy structure. New
Phytologist, 166(2):695–704.
Sun, J., Li, Y., Kang, S. B., and Shum, H.-Y. (2005). Sym-
metric stereo matching for occlusion handling. In
CVPR ’05: Proceedings of the 2005 IEEE Computer
Society Conference on Computer Vision and Pattern
Recognition (CVPR’05) - Volume 2, pages 399–406,
Washington, DC, USA. IEEE Computer Society.
Wedekind, J. (2002). Fokusserien-basierte rekonstruktion
von mikroobjekten. Master’s thesis, Universitat Karl-
sruhe.
Xiong, Y. and Shafer, S. (1993). Depth from focusing
and defocusing. Technical Report CMU-RI-TR-93-
07, Robotics Institute, Carnegie Mellon University,
Pittsburgh, PA.
Zhang, Z. (1999). Flexible camera calibration by viewing
a plane from unknown orientations. In International
Conference on Computer Vision (ICCV’99), Corfu,
Greece, pages 666–673.
Zhang, Z. (2000). A flexible new technique for camera cal-
ibration. IEEE Transactions on Pattern Analysis and
Machine Intelligence 22, (11):1330–1334.
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