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information can also be used as an additional tool for
robustness improvement, since the calibrated projector can be
regarded as a camera which emits the image signals rather than
receiving them (active triangulation).
6. CONCLUSIONS
The major advantage of the technique described in this paper is
that points can be matched with high accuracy simply and
therefore quickly relative to the methods reviewed in section 1.
Digital close range photogrammetry with structured light can be
used in a trinocular vision system for highly accurate wound
measurement. Almost all kind of ambiguities in point
correspondence can be resolved provided the criteria mentioned
in the proposed method are fulfilled, namely accurate
calibration, proper pattern design in terms of size and density,
appropriate system configuration, reliable image segmentation
and point detection, and establishment of reasonable cost
function for judging multiple matches. The experiments prove
that a robust image correspondence establishment with 95%
correct matches is achievable.
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