A 3-dimensional Camera Calibration Algorithm for Underwater Motion Analysis with Refraction Correction Capability
نویسنده
چکیده
INTRODUCTION The DLT (Direct Linear Transformation) algorithm, the most frequently used calibration algorithm, is based on the so-called collinearity condition; i.e. the object, image, and projection center form a straight line. This condition, however, does not hold in an underwater analysis setting due to the nonlinear image deformation caused by refraction at the water-air interface (Figure 1) [1]. The immediate outcome of the image deformation is an increased calibration/reconstruction error when compared to its above-water counterpart.
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تاریخ انتشار 2005