In this paper we describe a vehicle borne data acquisition system for urban environments and associated3ddata management and interactive rendering software. The data acquisition system is capable of acquire 3ddata ...
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ISBN:
(纸本)0769522238
In this paper we describe a vehicle borne data acquisition system for urban environments and associated3ddata management and interactive rendering software. The data acquisition system is capable of acquire 3ddata from urban areas with centimetre resolution including automatic capturing of colour. The system includes a management and interactive rendering software which is designed to cope with the huge quantities of data generated by the acquisition system. It uses out-of-core pre-processing to transform data into octrees. Real-time interactive rendering is achieved by using novel techniques such as front-to-back octree traversal, occlusion query and speculative pre-fetching. The paper presents the results of the described techniques applied to large public areas including the City Centre of Verona, Italy.
This paper describes the work performed for the ARCHEOGUIdE (Augmented Reality-based Cultural Heritage On-site GUIdE) project. ARCHEOGUIdE is funded by the EU 1ST framework (1ST-1999-11306), and pursued by a consortiu...
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ISBN:
(纸本)0769515223
This paper describes the work performed for the ARCHEOGUIdE (Augmented Reality-based Cultural Heritage On-site GUIdE) project. ARCHEOGUIdE is funded by the EU 1ST framework (1ST-1999-11306), and pursued by a consortium of European organisations. It delivers an interactive, personalized, augmented reality, (A R) guide for the visualization of ruined archaeological sites. It is based on mobile real-time computing, networking and3dvisualization. Its users are presented with monument reconstructions, navigation aid and historical information in a user-friendly way through the use of multi-modal interaction techniques. The key features of the system are a novel hybrid position and orientation tracking technique used in determining the user's viewpoint, navigation aid, outdoor operation, and real-time 3dvisualization of monuments, artifacts, and life. This paper presents examples of the system's use at the archaeological site of Ancient Olympia in Greece.
As products of second-order computations, estimations of principal curvatures are highly sensitive to noise. due to the availability of more accurate 3d range imaging equipment, evaluation of existing algorithms for t...
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ISBN:
(纸本)0769515215;0769515223
As products of second-order computations, estimations of principal curvatures are highly sensitive to noise. due to the availability of more accurate 3d range imaging equipment, evaluation of existing algorithms for the extraction of these invariants and other useful features from discrete 3ddata, is now relevant. The work presented here, makes some subtle but very important modifications to two such algorithms, originally suggested by Taubin [14] and Chen and Schmitt [2]. The algorithms have been adjusted to deal with real discrete noisy range data. The results of this implementation were evaluated in a series of tests on synthetic and real input yielding reliable estimations. Our conclusion is that with current scanning technology and the algorithms presented here, reliable estimates of the principal curvatures and the darboux frame can be extracted from real data and used in a variety of more comprehensive tasks.
Previous works have shown that the ear is a good candidate for a human biometric. However in prior work, the pre-processing of ear images has been a manual process. Also, prior algorithms were sensitive to noise in th...
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ISBN:
(纸本)9780769528250
Previous works have shown that the ear is a good candidate for a human biometric. However in prior work, the pre-processing of ear images has been a manual process. Also, prior algorithms were sensitive to noise in the data, especially that caused by hair and earrings. We present a novel solution to the automated cropping of the ear and implement it in an end-to-end solution for biometric recognition. We demonstrate our automatic recognition process with the largest study to date in ear biometrics, 415 subjects, achieving a rank one recognition rate of 97.6%. This work represents a breakthrough in ear biometrics and paves the way for commercial quality, fully automatic systems.
We introduce a generic and e cient method for 2d and3d shape estimation via density fields. Our method models shape as a density map and uses the notion of density to fit a model to a rapidly computed occupancy map o...
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ISBN:
(纸本)0769515223
We introduce a generic and e cient method for 2d and3d shape estimation via density fields. Our method models shape as a density map and uses the notion of density to fit a model to a rapidly computed occupancy map of the foreground object. We show how to utilize hierarchical (pyramid-like) object segmentation data to regularize a hierarchical model fitting. With primary focus on estimating 3d shapes of non-rigid articulated objects such as human bodies, we illustrate our approach with examples of c cient model fitting to 3d occupancy maps of human figures. We also discuss a number of extensions of our method to applications involving non-rigid object tracking and movement analysis.
We present a novel method for recovering the 3d-line structure of a scene from multiple widely separated views. Traditional optimization-based approaches to line-based structure from motion minimize the error between ...
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ISBN:
(纸本)9780769528250
We present a novel method for recovering the 3d-line structure of a scene from multiple widely separated views. Traditional optimization-based approaches to line-based structure from motion minimize the error between measured line segments and the projections of corresponding 3d lines. In such a case, 3d lines can be optimized using a minimum of 4 parameters. We show that this number of parameters can be further reduced by introducing additional constraints on the orientations of lines in a 3d scene. In our approach, 2d-lines are automatically detected in images with the assistance of an EM-based vanishing point estimation method which assumes the existence of edges along mutally orthogonal vanishing directions. Each detected line is automatically labeled with the orientation (e.g. vertical, horizontal) of the 3d line which generated the measurement, and it is this additional knowledge that we use to reduce the number of degrees of freedom of 3d lines during optimization. We present 3d reconstruction results for urban scenes based on manually established feature correspondences across images.
This paper presents a framework for the synthesis of stereoscopic video using as input only a monoscopic image sequence. Initially, bi-directional 2d motion estimation is performed, which is followed by an efficient m...
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ISBN:
(纸本)0769522238
This paper presents a framework for the synthesis of stereoscopic video using as input only a monoscopic image sequence. Initially, bi-directional 2d motion estimation is performed, which is followed by an efficient method for the reliable tracking of object contours. Rigid3d motion and structure is recovered utilizing extended Kalman filtering. Finally, occlusions are dealt with a novel Bayesian framework, which exploits future information to correctly reconstruct occluded areas. Experimental evaluation shows that the layered object scene representation, combined with the proposed methods for object tracking throughout the sequence and occlusion handling, yields very accurate results.
In this paper, we propose a method for 3d-model retrieval from one or more photos. This method provides an "optimal" selection of 2d views to represent a 3d-model, and a probabilistic Bayesian method for 3d-...
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ISBN:
(纸本)9780769528250
In this paper, we propose a method for 3d-model retrieval from one or more photos. This method provides an "optimal" selection of 2d views to represent a 3d-model, and a probabilistic Bayesian method for 3d-model retrieval from realistic photos and sketches using these views. The characteristic view selection algorithm is based on an adaptive clustering algorithm and uses statistical model distribution scores to select the optimal number of views. We also introduce a Bayesian approach to score the probability of correspondence between the queries and the 3d-models. We present our results on the Princeton 3d Shape Benchmark database (1814 3d-models) and 50 photos (real photographs, sketches, synthesised images). A practical on-line 3d-model retrieval system based on our approach is available on the web to asset our results [1].
A 3-dimensional (3-d) object modeling technique with mesh simplification and refinement based resolution adjustment is proposed in this paper. Polygonal models which are widely utilized in the modeling of 3-d objects ...
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ISBN:
(纸本)0769522238
A 3-dimensional (3-d) object modeling technique with mesh simplification and refinement based resolution adjustment is proposed in this paper. Polygonal models which are widely utilized in the modeling of 3-d objects are taken as basis, making use of the polygonal structure and vertex coordinates for the display of 3-d models. The amount of polygons and vertices of a model is proportional to the resolution as well as data quantity. In other words the resolution anddata increases with the number of polygons. In this paper, it is proposed to utilize resolution, and hence data amount, adjustable 3-d modeling so that model resolution and transmitteddata amount can be regulated according to access constraints.
This paper presents a computer vision stereo based interface to navigate inside a 3-d Internet city, using bode, gestures. A wide-baseline stereo pair of cameras is used to obtain 3-d body, models of the user's ha...
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ISBN:
(纸本)0769515223
This paper presents a computer vision stereo based interface to navigate inside a 3-d Internet city, using bode, gestures. A wide-baseline stereo pair of cameras is used to obtain 3-d body, models of the user's hands and head in a small desk-area environment. The interface feeds this information to an HMM gesture classifier to reliably recognize the user's browsing commands. To illustrate the features of this interface we describe its application to our 3-d Internet browser which facilitates the recollection of information by organizing and embedding it inside a virtual city through which the user navigates.
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