Results 1 
6 of
6
Mean shift: A robust approach toward feature space analysis
 In PAMI
, 2002
"... A general nonparametric technique is proposed for the analysis of a complex multimodal feature space and to delineate arbitrarily shaped clusters in it. The basic computational module of the technique is an old pattern recognition procedure, the mean shift. We prove for discrete data the convergence ..."
Abstract

Cited by 2375 (40 self)
 Add to MetaCart
(Show Context)
A general nonparametric technique is proposed for the analysis of a complex multimodal feature space and to delineate arbitrarily shaped clusters in it. The basic computational module of the technique is an old pattern recognition procedure, the mean shift. We prove for discrete data the convergence of a recursive mean shift procedure to the nearest stationary point of the underlying density function and thus its utility in detecting the modes of the density. The equivalence of the mean shift procedure to the Nadaraya–Watson estimator from kernel regression and the robust Mestimators of location is also established. Algorithms for two lowlevel vision tasks, discontinuity preserving smoothing and image segmentation are described as applications. In these algorithms the only user set parameter is the resolution of the analysis, and either gray level or color images are accepted as input. Extensive experimental results illustrate their excellent performance.
Efficient Grouping under Perspective Skew
, 2001
"... We present an efficient grouping strategy for the detection of regular repetitions of planar (but not necessarily coplanar) patterns. At the heart of our system lie the fixed structures that typify the geometric transformations of the regularities. The approach unifies a number of grouping types tha ..."
Abstract

Cited by 14 (1 self)
 Add to MetaCart
We present an efficient grouping strategy for the detection of regular repetitions of planar (but not necessarily coplanar) patterns. At the heart of our system lie the fixed structures that typify the geometric transformations of the regularities. The approach unifies a number of grouping types that have traditionally been dealt with separately. It avoids the use of combinatorics in the search for pattern repetitions, through the combined use of invariants for hashingbased pattern matching on the one hand, and Hough transforms for the detection of the fixed structures on the other hand. In this paper we concentrate on planar homologies and elations in particular. Results on realworld scenes demonstrate the performance of the approach.
Grouping via the Matching of Repeated Patterns
 In Proc. CAPR
, 2001
"... In this contribution, a novel and robust, geometrybased grouping strategy is proposed. Repeated, planar patterns in special relative positions are detected. The grouping is based on the idea of fixed structures. These are structures such as lines or points that remain fixed under the transformation ..."
Abstract

Cited by 9 (0 self)
 Add to MetaCart
In this contribution, a novel and robust, geometrybased grouping strategy is proposed. Repeated, planar patterns in special relative positions are detected. The grouping is based on the idea of fixed structures. These are structures such as lines or points that remain fixed under the transformations mapping the patterns onto each other. As they define subgroups of the general group of projectivities, they significantly reduce the complexity of the problem. First, some initial matches are found by comparing local, a#nely invariant regions. Then, possible fixed structure candidates are hypothesized using a cascaded Hough transform. In a further step, these candidates are verified. In this paper, we concentrate on planar homologies, i.e. subgroups that have a line of fixed points and a pencil of fixed lines.
MultiView Reconstruction and Camera Recovery Using a Real or Virtual Reference Plane
, 2003
"... Reconstructing a 3dimensional scene from a set of 2dimensional images is a fundamental problem in computer vision. A system capable of performing this task can be used in many applications in robotics, architecture, archaeology, biometrics, human computer interaction and the movie and entertainmen ..."
Abstract
 Add to MetaCart
Reconstructing a 3dimensional scene from a set of 2dimensional images is a fundamental problem in computer vision. A system capable of performing this task can be used in many applications in robotics, architecture, archaeology, biometrics, human computer interaction and the movie and entertainment industry.
Selfcalibrating Cameras . . .
, 2008
"... This thesis addresses the automatic calibration of two static surveillance cameras in a manmade world with orthogonal and parallel structures and a common ground plane. An approach is taken where the calibration of the interior orientation, the undistortion of the lens and the calibration of a cam ..."
Abstract
 Add to MetaCart
This thesis addresses the automatic calibration of two static surveillance cameras in a manmade world with orthogonal and parallel structures and a common ground plane. An approach is taken where the calibration of the interior orientation, the undistortion of the lens and the calibration of a camera’s rotation to the world perform before calibrating the camera centers, which allows methods that work in slightly overlapping as in nonoverlapping views. We present a new incremental calibration composed of Expectation Maximization and Simulated Annealing that uses the uncertainties of noisy line segments to process a video stream instead of a single image. The advantage of video is that orthogonal and parallel edge
unknown title
"... ABSTRACT⎯Logpolar coordinate image space is proposed as a solution for the problem of unbounded accumulator space in the automatic detection of vanishing points. The proposed method can detect vanishing points at high speed under small memory requirements, as opposed to conventional image space bas ..."
Abstract
 Add to MetaCart
(Show Context)
ABSTRACT⎯Logpolar coordinate image space is proposed as a solution for the problem of unbounded accumulator space in the automatic detection of vanishing points. The proposed method can detect vanishing points at high speed under small memory requirements, as opposed to conventional image space based methods. Keywords⎯Vanishing point detection, logpolar coordinate, image space. I.