In this paper we present a, geometric theory for reconstruction of surface models from sparse 3D data captured from N camera views which are consistent with the data visibility. Sparse 3D measurements of real scenes a...
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In this paper we present a, geometric theory for reconstruction of surface models from sparse 3D data captured from N camera views which are consistent with the data visibility. Sparse 3D measurements of real scenes are readily estimated from image sequences using structure-from-motion techniques. Currently there is no general method for reconstruction of 3D models of arbitrary scenes from sparse data. We introduce an algorithm for recursive integration of sparse all structure to obtain a consistent model. This algorithm is shown to converge to the real scene structure as the number of views increases and to have a. computational cost which is linear in the number of views. Results are presented for real and synthetic image sequences which demonstrate correct reconstruction for scenes containing significant occlusions.
The measurement of object reflectance from color images is carried out. Illumination and geometrical invariant properties are derived from a physical reflectance model based on the Kubelka-Munk theory. Invariance, dis...
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The measurement of object reflectance from color images is carried out. Illumination and geometrical invariant properties are derived from a physical reflectance model based on the Kubelka-Munk theory. Invariance, discriminative power and localization accuracy of the color invariants are extensively studied. Experiments show the different invariants to be highly discriminative while maintaining invariance properties.
This paper reports a visual system that recognizes 3D shapes of high speed moving objects. In this system, an active camera fixates a point on the moving object at the center of the image and tracks it. In this tracki...
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ISBN:
(纸本)0780363493
This paper reports a visual system that recognizes 3D shapes of high speed moving objects. In this system, an active camera fixates a point on the moving object at the center of the image and tracks it. In this tracking, other object points than the fixation point move in the image field depending on their relative depths to the fixated point. Based on this fact, we are able to reconstruct 3D object shape from the tracking images. We developed a simple algorithm to realize this reconstruction for real time processing. We utilize the relation between spatial and temporal change of image with respect to the object depths. For our purpose, it is important to obtain object shape quickly even if it will be rough one. We constructed a system that does not need complex and difficult imageprocessing.
In this paper, a novel scheme of extracting multiple illuminant directions from an image of a Lambertian sphere of known size is proposed. The illuminant direction detection process is based on the concept of critical...
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In this paper, a novel scheme of extracting multiple illuminant directions from an image of a Lambertian sphere of known size is proposed. The illuminant direction detection process is based on the concept of critical points introduced in the paper. We show that the illuminant directions have a close relationship to those critical points and that, by identifying those critical points as many as possible, illuminant directions may be recovered if certain conditions are satisfied. Our preliminary experimental results show that illumination information can be obtained accurately.
We will demonstrate our CVPR2000 paper 'Measurement of Color Invariants' for the cases of image retrieval based on query by example and for color image segmentation. Both are of importance in content based acc...
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We will demonstrate our CVPR2000 paper 'Measurement of Color Invariants' for the cases of image retrieval based on query by example and for color image segmentation. Both are of importance in content based access of image and video data. We demonstrate the usefulness of the proposed color invariants in image retrieval by example systems. We show that an image retrieval query should include the type of invariance expected in the result. We demonstrate such queries by using the 'imageSurf' retrieval system. Segmentation of images based on the proposed color invariants is demonstrated by the 'PicToVision' system. The system provides imageprocessing.functionality through the world wide web, and is publicly accessible at ***/research/isis/***.
We present two families of reflective surfaces that are capable of providing a wide field of view, and yet still approximate a perspective projection to a high degree. These surfaces are derived by considering a plane...
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ISBN:
(纸本)0769507042;0769507050
We present two families of reflective surfaces that are capable of providing a wide field of view, and yet still approximate a perspective projection to a high degree. These surfaces are derived by considering a plane perpendicular to the axis of a surface of revolution and finding the equations governing the distortion of the image of the plane in this surface. We then view this relation as a differential equation and prescribe the distortion term to be linear. By choosing appropriate initial conditions for the differential equation and solving it numerically, we derive the surface shape and obtain a precise estimate as to what degree the resulting sensor can approximate a perspective projection. Thus these surfaces act as computational sensors, allowing for a wide-angle perspective view of a scene without processing.the image in software. The applications of such a sensor should be numerous, including surveillance, robotics and traditional photography.
Intelligent Scissors and Intelligent Paint are complementary interactive image segmentation tools that allow a user to quickly and accurately select objects of interest. This demonstration provides a means for partici...
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Intelligent Scissors and Intelligent Paint are complementary interactive image segmentation tools that allow a user to quickly and accurately select objects of interest. This demonstration provides a means for participants to experience the dynamic nature of these tools.
We address the problem of rejecting false matches of points between two perspective views. Even the best algorithms for image matching make some mistakes and output some false matches. We present an algorithm for iden...
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ISBN:
(纸本)0769506623
We address the problem of rejecting false matches of points between two perspective views. Even the best algorithms for image matching make some mistakes and output some false matches. We present an algorithm for identification of the false matches between the views. The algorithm exploits the possibility of rotating one of the images to achieve some common behaviour of the correct matches. Those matches that deviate from this common behaviour turn out to be false matches. The statistical tool we use is the Mean Shift Mode Estimator. Our algorithm does not use in any way the image characteristics of the matched features. In particular it avoids problems that cause the false matches in the first place. The algorithm may be run as a post processing.step on output from any point matching algorithm. Use of the algorithm may significantly improve the ratio of correct matches to incorrect matches. On real images our algorithm has improved the percentage of correct matches from an initial 20%-30% to a final 70%-80%. For robust estimation algorithms which are later employed, this is a very desirable quality since it reduces significantly their computational cost. We present the algorithm, identify the conditions under which it works, and present results of testing it on both synthetic anf real images.
This Volume 1 of 2 of the conferenceproceedings contains 117 papers. Topics discussed include stereo vision, tracking, image retrieval, illumination, faces, shape and segmentation, shape pattern and statistics, motio...
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This Volume 1 of 2 of the conferenceproceedings contains 117 papers. Topics discussed include stereo vision, tracking, image retrieval, illumination, faces, shape and segmentation, shape pattern and statistics, motion and motion rendering, color and light, matching and recognition.
The design of an effective architecture for content-based retrieval from visual libraries requires careful consideration of the interplay between feature selection, feature representation, and similarity metric. We pr...
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The design of an effective architecture for content-based retrieval from visual libraries requires careful consideration of the interplay between feature selection, feature representation, and similarity metric. We present a solution where all the modules strive to optimize the same performance criteria: the probability of retrieval error. This solution consists of a Bayesian retrieval criteria (shown to generalize the most prevalent similarity metrics in current use) and an embedded mixture representation over a multiresolution feature space (shown to provide a good trade-off between retrieval accuracy, invariance, perceptual relevance of similarity judgments, and complexity). The new representation extends standard models (histogram and Gaussian) by providing simultaneous support for high-dimensional features and multi-modal densities and performs well on color, texture, and generic image databases.
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