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For computation of the epipolar geometry from central- omni-directional images, the use of the spherical camera model is essential. This is because the central-omnidirectional cameras are universally expressed as the spherical camera model when the intrinsic parameters of the cameras are calibrated. Geometrically, for corresponding points between two spherical images, there exists the same epipolar constraint as the conventional pinhole-camera model. Therefore, it is possible to use the conventional eight-point algorithm for recovering camera motion and 3D objects from two spherical images. In this paper, using the geometric properties on rotation of the spheres, we propose a method of the accurate computation based on the rectification of the spherical-camera images via the conventional eight-point algorithm. [ABSTRACT FROM AUTHOR]

We propose the algorithm for detecting great circles on images on a sphere using the Hough transform. Since our Hough transform on images on a sphere is derived on the basis of the duality, the Hough transform employs a dual sphere as the accumulator of the voting procedure. Furthermore, we propose a robust algorithm based on three-point Hough transform and the segmentation of points on the dual sphere using the metric defined on a sphere. [ABSTRACT FROM AUTHOR]

This paper focuses on variational image analysis on a sphere. Since a sphere is a closed Riemannian manifold with the positive constant curvature and no holes, a sphere has similar geometrical properties with a plane, whose curvature is zero. Images observed through a catadioptric system with a conic-mirror and a dioptric system with fish-eye lens are transformed to images on the sphere. Therefore, in robot vision, image analysis on the sphere is an essential requirement to the application of the omni-directional imaging system with conic-mirror and fish-eye lens for navigation and control. We introduce algorithms for optical flow computation for images on a sphere. [ABSTRACT FROM AUTHOR]

This paper focuses on variational optical flow computation for spherical images. It is said that some insects recognise the world through optical flow observed by their compound eyes, which observe spherical views. Furthermore, images observed through a catadioptric system with a conic mirror and a fish-eye-lens camera are transformed to images on the sphere. Spherical motion field on the spherical retina has some advantages for the ego-motion estimation of autonomous mobile observer. We provide a framework for motion field analysis on the spherical retina using variational method for image analysis. [ABSTRACT FROM AUTHOR]