matching
about ten
region to
ouple of
ompletely
ne, about
oximately
les of the
acquired
each side
> end, the
puted by
alibration
) points is
nm in the
ign
joints),
its)
As shown in figure 13 (top), the point cloud is very dense
(45,000 points) and the region of overlap of the two joined data
set can be observed in the center line of the face. To overcome
the redundant data and remove eventual outliers, Gaussian
filters (Borghese and Ferrari, 2000) are applied to the 3-D point
cloud and the data is afterwards thinned (see figure 13 bottom).
For surface measurement purposes, the computed 3-D point
cloud is satisfactory. In case of visualization, a complete model
of the face with texture has to be produced. A meshed surface is
therefore generated from the 3-D point cloud by 2.5-D
Delauney triangulation and to achieve photorealistic
visualization, the natural texture acquired by the color video
camera is draped over the model of the face. Figure 14 shows
the surface model, the texture image and two views of the
resulted face model with texture, figure 15 shows two other
examples of face models.
Figure 14. Photorealistic visualization; top: shaded surface
model and texture image; bottom: face model with texture
3. CONCLUSIONS
A process for an automated measurement of the human face
from multi-images acquired by five synchronized CCD cameras
has been presented. The main advantages of this method are its
flexibility, the reduced costs of the hardware and the possibility
to perform surface measurement of dynamic events.
ACKNOWLEDGEMENT
The work reported here was funded in part by the Swiss
National Science Foundation.
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Figure 15. Photorealistic visualization; two other examples of face models
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