OpenRaiser/Intern-Atlas huggingface dataset:
A dynamic depth extraction method
Authors: Terunori Mori, Masanobu Yamamoto
Venue: ICCV
Year: 1990

A dynamic depth extraction method (DDEM) is proposed, which tracks the time taken for a detected edge to move a known distance on the image plane and hence is able to calculate depth. Experimental results for three vertical bars of differing depth show the mean depths obtained were almost the same as those obtained from direct measurement. The fluctuation of obtained depth was about 3.6%, which corresponds to one half frame difference in matching time of the near bar. The DDEM was also successfully applied to a complicated room.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Estimation of shape, reflection coefficients and illuminant direction from image sequences
Authors: Naoki Mukawa
Venue: ICCV
Year: 1990

A comprehensive scene analysis algorithm that extracts object shape, reflection coefficients and illuminant direction from just sequential images expressed as luminance values is proposed. The proposed algorithm uses an optical model consisting of a light source, an object and a viewer. Within this framework, the algorithm allows for diffuse and specular reflection, variations in object reflection coefficients and shading. The first phase of the algorithm calculates three values: (1) the variation of inner product of illuminant direction and surface normal before and after motion, and (2) the variation of shading, as well as (3) the motion field. The second phase uses these values to recover not only object shape but also illuminant direction and reflection coefficients of the surface. The algorithm's performance is confirmed through computer simulation. The reflection coefficients and the light source direction are estimated accurately while the recovered shape contains some errors.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The evolution and testing of a model-based object recognition system
Authors: Joseph L. Mundy, Aaron Heller
Venue: ICCV
Year: 1990

A benchmark evaluation test of a model-based recognition system is discussed. The system was tested on a series of aerial reconnaissance images to evaluate recognition performance on the task of airfield monitoring. The effectiveness of the model pose constraint for recognition is discussed as well as an approach for selection of model features. The use of distance transforms for model hypothesis confirmation is also discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Object recognition by a Hopfield neural network
Authors: Nasser M. Nasrabadi, Wei Li 0047, Chang Y. Choo
Venue: ICCV
Year: 1990

A model-based recognition method is introduced which is formulated as an optimization problem. An energy function is derived which represents the constraints on the best solution in order to find the best match. A two-dimensional binary Hopfield neural network is implemented to minimize the energy function. The state of each neuron in the Hopfield network represents the possibility of a match between a node in the model graph and a node in the scene graph. >
Recovering 3D motion and structure from stereo and 2D token tracking cooperation
Authors: Nassir Navab, Rachid Deriche, Olivier D. Faugeras
Venue: ICCV
Year: 1990

An investigation is conducted of the relationships that exist between the three-dimensional structure and kinematics, of a line moving rigidly in space and the two-dimensional structure and kinematics (optical flow) of its image in one or two cameras. The authors establish the fundamental equations that relate its three-dimensional motion to its observed image motion. They then assume that stereo matches have been established between image segments and show how the estimation of the optical flows in the two images can be used to compute part of the kinematic screw of the corresponding 3-D line. The equations are linear and provide a very simple way to estimate the full kinematic screw, if several lines of the same object are available. Experimental results using synthetic and real data are presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The 2.1-D sketch
Authors: Mark Nitzberg, David Mumford
Venue: ICCV
Year: 1990

A model is described for image segmentation that tries to capture the low-level depth reconstruction exhibited in early human vision, giving an important role to edge terminations. The problem is to find a decomposition of the domain D of an image that has a minimum of disrupted edges-junctions of edges, crack tips, corners, and cusps-by creating suitable continuations for the disrupted edges behind occluding regions. The result is a decomposition of D into overlapping regions R/sub 1/ union . . . union R/sub n/ ordered by occlusion, which is called the 2.1-D sketch. Expressed as a minimization problem, the model gives rise to a family of optimal contours, called nonlinear splines, that minimize length and the square of curvature. These are essential in the construction of the 2.1-D sketch of an image, as the continuations of disrupted edges. An algorithm is described that constructs the 2.1-D sketch of an image, and gives results for several example images. The algorithm yields the same interpretations of optical illusions as the human visual system.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A locally adaptive window for signal matching
Authors: Masatoshi Okutomi, Takeo Kanade
Venue: ICCV
Year: 1990

The authors presents a signal matching algorithm that can select an appropriate window size adaptively so as to obtain both precise and stable estimation of correspondences. A statistical model is presented for disparity variation within a window, and it is used to establish a link between the window size and the uncertainty of the computed disparity. This makes it possible to choose the window size that minimizes uncertainty in the disparity computed at each point. A theory is presented for the model and the resultant algorithm, together with analytical and experimental results that demonstrate their effectiveness.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Photometric motion
Authors: Alex Pentland
Venue: ICCV
Year: 1990

Photometric changes can lead to severe errors in shape recovery if not correctly accounted for. The author shows that photometric motion can be used to obtain a closed-form solution for both surface shape and reflectance and discusses how this solution can be used to enhance the performance of geometrically based structure-from-motion algorithms. A simple biological mechanism is demonstrated that accomplishes the recovery of both shape and reflectance.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Hypothesis testing: a framework for analysing and optimising Hough transform performance
Authors: John Princen, John Illingworth, Josef Kittler
Venue: ICCV
Year: 1990

A formal, quantitative approach to designing optimal Hough transform (HT) algorithms is proposed. This approach takes the view that a HT is a hypothesis testing method. This view allows the performance of HT algorithms to be quantified. The power function, which gives the probability of rejection as a function of the underlying parametric distribution of data points, is shown to be the fundamentally important characteristic of HT behavior. Attempting to make the power function narrow is a formal approach to optimizing HT performance. To illustrate how this framework is useful the particular problem of line detection is discussed. It is shown that the hypothesis testing framework leads to a redefinition of HT in which the values are a measure of the distribution of points around a curve rather than the number of points on a curve. The solution to many HT design problems can be posed within the framework, including optimal quantizations and optimum sampling of the parameter space. Consideration is given to the design of optimum 1-D filters which can be used to sharpen the peak structure in parameter space. Results on several real images illustrate the improvements obtained.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Detection of interest points using symmetry
Authors: Daniel Reisfeld, Haim J. Wolfson, Yehezkel Yeshurun
Venue: ICCV
Year: 1990

An operator based on the intuitive motion of symmetry, which effectively locates interest points in real time and can be incorporated also in active visual systems, is introduced. The results of its operation agree with some psychophysical evidence concerning symmetry as well as evidence concerning fixation points. The operator can be applied successfully without prior knowledge of the world. Combining the operator with some preconceptions about the image is a powerful tool for feature detection in intricate natural scenes. The localization of faces and facial features in real time is demonstrated on detailed and noisy pictures.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Terrain matching by analysis of aerial images
Authors: Jeffrey J. Rodríguez, Jake K. Aggarwal
Venue: ICCV
Year: 1990

A terrain matching algorithm has been developed for use in a passive aircraft navigation system. A sequence of aerial, optical images is matched to a reference digital map of the three-dimensional terrain. Stereo analysis of successive images results in the recovery of an elevation map of the observed terrain. A 'cliff map' is then used as a novel, compact representation of the terrain surface. The position and heading of the aircraft are determined via a terrain matching algorithm that locates the observed cliff map within the reference cliff map. Novel results using real terrain data and on implementation of a real stereo algorithm provide an important extension to previous results using simulated stereo.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Segmenting curves into elliptic arcs and straight lines
Authors: Paul L. Rosin, Geoff A. W. West
Venue: ICCV
Year: 1990

A method is described for segmenting edge data into a combination of straight lines and elliptic arcs. The two-stage process first segments the data into straight line segments. Ellipses are then fitted to the line data. This is much faster than curve fitting directly to pixel data since the lines provide a great reduction in data. Segmentation is performed in the paradigm suggested by D.G. Lowe (1987). A measure of significance is defined that produces a scale-invariant description and allows the replacement of sequences of line segments by ellipses without requiring any thresholds. A method for fitting ellipses to arbitrary curves, essential for this algorithm, has been developed, based on an iterative Kalman filter. This is guaranteed to produce an elliptical fit even though the best conic fit may be a hyperbola or parabola.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Segmentation of 3D range images using pyramidal data structures
Authors: Bikash Sabata, Farshid Arman, Jake K. Aggarwal
Venue: ICCV
Year: 1990

Given a 3D range image of a scene containing multiple arbitrarily shaped objects, the authors segment the scene into homogeneous surface patches. A novel modular framework for the segmentation task is proposed. In the first module, over-segmentation is achieved using zeroth and first order local surface properties. The segmentation is then refined in the second module using high order surface representations dictated by the high level vision tasks. The procedure has been applied successfully to many range images, five of which are presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Computing the visual potential of an articulated assembly of parts
Authors: Maha Sallam, John H. Stewman, Kevin W. Bowyer
Venue: ICCV
Year: 1990

Consideration is given to a generalization of the aspect graph concept which is applicable to objects which may have articulated connection between their (rigid) parts. This generalization is a major step forward in terms of applying the aspect graph concept to a larger and more realistic domain of objects. An algorithm for computing the generalized aspect graph is described, and an example is analyzed in detail.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Representation and the dimensions of shape deformation
Authors: E. Saud
Venue: ICCV
Year: 1990

The author shows how a representation for visual shape can exploit knowledge of the ways in which shapes are related by deformation of their geometries. The approach is based not on generic rules or principles for interpreting shape deformation in general, but instead relies on careful analysis of shapes occurring in a specific domain. The representation uses a relatively large vocabulary of simple geometric descriptors, each of which resembles a template that deforms as a mechanical linkage. Because these descriptors are designed to name significant aspects of spatial deformation known to structure the target domain, the representation provides a rich vocabulary with which to perform shape classification, comparison, and other visual tasks involving subtle distinctions about objects' forms. The approach is illustrated for the two-dimensional shape world of fish dorsal fins.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Description and reconstruction from image trajectories of rotational motion
Authors: Harpreet S. Sawhney, John Oliensis, Allen R. Hanson
Venue: ICCV
Year: 1990

A novel technique is presented for reconstructing the 3-D structure, and motion, of a scene undergoing relative rotational motion with respect to the camera. Given image correspondences of point features tracked over many frames, first, a grouping algorithm developed which exploits spatio-temporal constraints of the common motion to achieve a reliable description of discrete point correspondences as curved trajectories (general conics in the case of rotational motion) in the image plane. In contrast, trajectories fitted to points independent of each other lead to arbitrary image descriptions and very inaccurate 3-D parameters. Second, a novel closed-form solution, under perspective projection, for the 3-D motion and location of points from the computed image trajectories is presented. Both stages are applied to real image sequences with good results.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Modeling the rim appearance
Authors: W. Brent Seales, Charles R. Dyer
Venue: ICCV
Year: 1990

A viewer-centered approach is presented to modeling the geometry of the visible occluding contour of solid 3-D shape. The rim appearance representation models the exact appearance of the occluding contour formed by the edges of a polyhedron. An algorithm is presented for constructing the rim appearance representation. Bounds on space and time are given, and implementation results show that the rim appearance representation is significantly smaller than both the aspect graph and the asp representation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Towards a computational theory of model based vision and perception
Authors: Haim Shvaytser
Venue: ICCV
Year: 1990

When given partial data, a model based approach requires that pictures consistent with the model are chosen as plausible interpretations of the data. The author presents a computational theory that relates degrees of freedom in such models to the number of pixels that carry useful information. It is shown that in models with a finite number of degrees of freedom it is always possible to find a consistent interpretation from a finite number of pixels.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Viewpoint invariant recovery of visual surfaces from sparse data
Authors: Robert L. Stevenson, Edward J. Delp
Venue: ICCV
Year: 1990

A new algorithm is described for the reconstruction of visual surfaces from sparse data. An important aspect of this algorithm is that the surface estimated from the sparse data is approximately invariant with respect to rigid transformation of the surface in three-dimensional space. To form a surface estimate which is invariant with respect to viewpoint the stabilizing information is based on invariant surface characteristics. With appropriate approximations this results in a convex functional which must be minimized. The relationship of this algorithm to several previously proposed reconstruction algorithms is discussed, and several examples are given which demonstrate the effectiveness of the proposed algorithm in reconstructing viewpoint invariant surface estimates.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Reconstructing line drawings from wings: the polygonal case
Authors: George C. Stockman, Greg Chungmou Lee, Sei-Wang Chen
Venue: ICCV
Year: 1990

Object wings are 2 1/2-D primitives encoding fragments of object boundary and the adjacent surfaces. The adequacy of wing representation for polygonal scenes is demonstrated in the sense that if a wing representation has been derived from the image of polygons, the spatial structure of the view can be uniquely recovered. In other words, it is possible to reconstruct all visible parts of the scene based on the given wing representation-all visible vertices the equations of all visible faces, and the completely labeled line drawing of the scene. It is shown that not only can most origami and polyhedral objects be handled but also that many views considered 'accidental' by other researchers can be handled as well.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Curved inertia frames and the skeleton sketch: Finding salient frames of reference
Authors: J. Brian Subirana-Vilanova
Venue: ICCV
Year: 1990

The author introduces curved inertia frames (CIFs), a new definition of curved axes of inertia. A scheme is given for finding a frame of reference of a shape in an image based on such a definition and the author discusses how the frame can be used to describe the shape. The scheme assigns a saliency measure to each component of the reference frame that is a measure of its relevance, so that large and central parts play a more central role in the description of the shape. The scheme also computes a major axis that is used to organize the description of the shape, so that a canonical description can be obtained. One of the features of the scheme is its tolerance to noisy and spurious data. Several perceptual phenomena observed in humans such as grouping based on symmetry and environment bias in shape description can be reproduced naturally in this scheme.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Indexing via color histograms
Authors: Michael J. Swain, Dana H. Ballard
Venue: ICCV
Year: 1990

This paper shows color histograms to be stable object representations over change in view, and demonstrates that they can differentiate among a large number of objects. The authors introduce a technique called histogram intersection for efficiently matching model and image histograms. Color can also be used to search for the location of an object. An algorithm called histogram backprojection performs this task efficiently in crowded scenes.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Direct recovery of motion and shape in the general case by fixation
Authors: M. Ali Taalebinezhaad
Venue: ICCV
Year: 1990

A direct method called fixation is introduced for solving the general motion vision problem. This method results in a constraint equation between translational and rotational velocities that in combination with the brightness-change constraint equation solves the general motion vision problem, arbitrary motion relative to an arbitrary rigid scene. Avoiding correspondence and optical flow has been the motivation behind the direct methods. Recently, direct motion vision methods have used the brightness-change constraint equation for solving special cases such as known depth, pure translation or know rotation, pure rotation, and planar world. In contrast to those solutions, the fixation method does not push such severe restrictions on the motion or the environment.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Simultaneous estimation of shape and reflectance maps from photometric stereo
Authors: Hemant D. Tagare, Rui J. P. de Figueiredo
Venue: ICCV
Year: 1990

The authors address the issue of whether the shape of an object and certain parameters of its reflectance map can be jointly estimated using photometric stereo. This problem has been addressed in the literature for the case where the Lambertian and non-Lambertian components in the image can be easily separated. The authors do not assume each separability. They highlight some aspects of the detailed solution to the above problem.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Representing surface curvature discontinuities on curved surfaces
Authors: Hiromi T. Tanaka, Daniel T. L. Lee
Venue: ICCV
Year: 1990

A representation scheme is presented for shapes of three-dimensional curved objects whose surface curvatures are not continuous at all points, i.e., surfaces with C/sup 1/ continuity only. A class of surface curves and points called surface structure descriptors for this representation are defined. These descriptors consist of subsets of lines of curvature and their intersections and are based on local descriptions of smooth surfaces. The surface structure curves are derived from the zero-crossings, asymptotes and gradient directions of the Gaussian and mean curvatures of the surface. A smooth surface sketch in terms of the geometrical structures of enclosing boundaries of bumps and dents, ridge and valley lines, and peaks and pits is developed. A hierarchical description of curved surfaces that leads to a global shape representation of the object is obtained from these descriptors. To handle the discontinuities of surface curvatures, a computational scheme is introduced in which gradient directions of surface curvatures at the discontinuities can be inferred. Simulation results on the computation of these descriptors from curved surfaces are shown. Potential applications of these representation schemes in computer vision tasks are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>