The mainstream approach to estimate epipolar geometry from two views requires matching the projections of at least 4 non-coplanar points in the scene, assuming a full projective camera model. Our work deviates from this in three respects: affine camera, planar scene and active contour tracking instead of point matching. Using results in Projective Geometry, we prove that the affine epipolar dir...

An active contour is used to track a target in a sequence recorded by a walking robot in an unstructured scene . The deformations of the contour are analysed in order to extract the robot’s egomotion, from which we compute the epipolar geometry that guides the matching between different views of the scene. The results prove that the proposed solution is a promising alternative to the prevalent ...

A method for computing the 3D camera motion (the egomotion) in a static scene is described, where initially a detected 2D motion between two frames is used to align corresponding image regions. We prove that such a 2D registration removes all effects of camera rotation, even for those image regions that remain misaligned. The resulting residual parallax displacement field between the two region...

In this paper, we present a visual control approach consisting in a switching control scheme based on epipolar geometry. The method facilitates a classical teach-by-showing approach where a reference image is used to control the robot to the desired pose (position and orientation). As a result of our proposal a mobile robot carries out a smooth trajectory towards the target and the steering str...

This paper proposes a visual servoing algorithm for mobile robot navigation based on the epipolar geometry retrieved by object profiles. The main motivation for this approach is that for unstructured scenes the task of solving correspondences is definitely a harder task than contour detection. An unstructured three-dimensional (3-D) scene consists mainly of objects whose most important 2-D feat...

We propse the one-line search (OLS) method for estimating the three-dimensional (3-D) model of an object from a sequence of images where the object is visible from different points of view. The OLS method estimates each 3-D point through a OLS along the ray defined by the camera center and its two-dimensional (2-D) image projection in one view by maximizing a photo-consistency index built with ...

For face and facial expression recognition, it is necessary to estimate head motion in order to track a head continuously. This paper proposes a new method for estimating head motion using the epipolar geometry of a weak perspective projection model. In this method, rst, the head region is segmented from the gradient of a luminance, by approximating the contour of the head as a circle. Then, fe...

We present a system locating the contour of an iris in space using robust active ellipse search and correspondenceless stereo. Robust iris location is the basis for gaze estimation and tracking, and, as such, an essential module for augmented and virtual reality environments. The system implements a robust active ellipse search based on a multi-scale contour detection model. The search is carri...

Most approaches to camera motion estimation from image sequences require matching the projections of at least 4 non-coplanar points in the scene. The case of points lying on a plane has only recently been addressed, using mainly projective cameras. We here study what can be recovered from two uncalibrated views of a planar contour under affine viewing conditions. We prove that the affine epipol...