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Equidistant fisheye projection function representation. 

Equidistant fisheye projection function representation. 

Context in source publication

Context 1
... d ) on the image plane, which is the radial distance in equidistant projection, is directly proportional to incident ray's angle. It is equivalent to arc segment's length, which is located between the z-axis and the projection ray of point P on the sphere in Figure 5 [62]. ...

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... In general, calibration methods are based on points and lines, patterns and selfcalibration procedures. There are some studies related to calibration applied to fisheye lenses [73][74][75][76][77][78][79][80] and 360-degree cameras [51,69,70,[81][82][83], which have improved geometric results. Other studies showed comparisons between several types of cameras (perspective, fisheye, etc.) [34,84]. ...
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... Fisheye lenses utilize specific mapping (stereographic, equidistant, equisolid angle, orthogonal), which provides the images a characteristic convex non-rectilinear appearance. 28 These specific lenses have a wide range of applications due to their ability to provide rich visual information, including the genera-tion of augmented or virtual reality, 29 improving the performance of intelligent robot vision systems, 30 and simplifying the complexity of surveillance systems. 31 Various correction models have been proposed to rectify the distortion of fisheye lenses. ...
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... Fisheye lenses are ultra-wide angle lenses capable of taking wide panoramic or hemispheric images, however, they incorporate a significant optical distortion into the process. Fisheye lenses utilise specific mapping (stereographic, equidistant, equisolid angle, orthogonal) which lands the images a characteristic convex non-rectilinear appearance 28 . These specific lenses have a wide range of applications due to their ability to provide rich visual information, including the generation of augmented or virtual reality 29 , improving the performance of intelligent robot vision systems 30 , and simplifying the complexity of surveillance systems 31 . ...
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