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157
View management for virtual and augmented reality
, 2001
"... We describe a viewmanagement component for interactive 3D user interfaces. By view management, we mean maintaining visual constraints on the projections of objects on the view plane, such as locating related objects near each other, or preventing objects from occluding each other. Our viewmanageme ..."
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Cited by 111 (19 self)
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We describe a viewmanagement component for interactive 3D user interfaces. By view management, we mean maintaining visual constraints on the projections of objects on the view plane, such as locating related objects near each other, or preventing objects from occluding each other. Our viewmanagement component accomplishes this by modifying selected object properties, including position, size, and transparency, which are tagged to indicate their constraints. For example, some objects may have geometric properties that are determined entirely by a physical simulation and which cannot be modified, while other objects may be annotations whose position and size are flexible. We introduce algorithms that use upright rectangular extents to represent on the view plane a dynamic and efficient approximation of the occupied space containing the projections of visible portions of 3D objects, as well as the unoccupied space in which objects can be placed to
Label Placement by Maximum Independent Set in Rectangles
 COMPUTATIONAL GEOMETRY
, 1998
"... Motivated by the problem of labeling maps, we investigate the problem of computing a large nonintersecting subset in a set of n rectangles in the plane. Our results are as follows. In O(n log n) time, we can find an O(log n)factor approximation of the maximum subset in a set of n arbitrary axispa ..."
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Cited by 91 (6 self)
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Motivated by the problem of labeling maps, we investigate the problem of computing a large nonintersecting subset in a set of n rectangles in the plane. Our results are as follows. In O(n log n) time, we can find an O(log n)factor approximation of the maximum subset in a set of n arbitrary axisparallel rectangles in the plane. If all rectangles have unit height, we can find a 2approximation in O(n logn) time. Extending this result, we obtain a (1 + l/k)approximation in time O(n logn + n 2k1) time, for any integer k/> 1. © 1998 Elsevier Science B.V. All rights reserved.
Direct Annotation: A DragandDrop Strategy for Labeling Photos
, 2000
"... Annotating photos is such a timeconsuming, tedious and errorprone data entry task that it discourages most owners of personal photo libraries. By allowing users to drag labels such as personal names from a scrolling list and drop them on a photo, we believe we can make the task faster, easier and ..."
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Cited by 78 (13 self)
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Annotating photos is such a timeconsuming, tedious and errorprone data entry task that it discourages most owners of personal photo libraries. By allowing users to drag labels such as personal names from a scrolling list and drop them on a photo, we believe we can make the task faster, easier and more appealing. Since the names are entered in a database, searching for all photos of a friend or family member is dramatically simplified. We describe the user interface design and the database schema to support direct annotation, as implemented in our PhotoFinder prototype. Keywords: direct annotation, direct manipulation, graphical user interfaces, photo libraries, draganddrop, label placement 1. Introduction Adding captions to photos is a timeconsuming and error prone task for professional photographers, editors, librarians, curators, scholars, and amateur photographers. In many professional applications, photos are worthless unless they are accurately described by date, time, loc...
Fusion Moves for Markov Random Field Optimization
"... The efficient application of graph cuts to Markov Random Fields (MRFs) with multiple discrete or continuous labels remains an open question. In this paper, we demonstrate one possible way of achieving this by using graph cuts to combine pairs of suboptimal labelings or solutions. We call this combi ..."
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Cited by 67 (5 self)
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The efficient application of graph cuts to Markov Random Fields (MRFs) with multiple discrete or continuous labels remains an open question. In this paper, we demonstrate one possible way of achieving this by using graph cuts to combine pairs of suboptimal labelings or solutions. We call this combination process the fusion move. By employing recently developed graph cut based algorithms (socalled QPBOgraph cut), the fusion move can efficiently combine two proposal labelings in a theoretically sound way, which is in practice often globally optimal. We demonstrate that fusion moves generalize many previous graph cut approaches, which allows them to be used as building block within a broader variety of optimization schemes than were considered before. In particular, we propose new optimization schemes for computer vision MRFs with applications to image restoration, stereo, and optical flow, among others. Within these schemes the fusion moves are used 1) for the parallelization of MRF optimization into several threads; 2) for fast MRF optimization by combining cheaptocompute solutions; and 3) for the optimization of highly nonconvex continuouslabeled MRFs with 2D labels. Our final example is a nonvision MRF concerned with cartographic label placement, where fusion moves can be used to improve the performance of a standard inference method (loopy belief propagation).
NewsStand: A New View on News
, 2008
"... News articles contain a wealth of implicit geographic content that if exposed to readers improves understanding of today’s news. However, most articles are not explicitly geotagged with their geographic content, and few news aggregation systems expose this content to users. A new system named NewsSt ..."
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Cited by 54 (25 self)
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News articles contain a wealth of implicit geographic content that if exposed to readers improves understanding of today’s news. However, most articles are not explicitly geotagged with their geographic content, and few news aggregation systems expose this content to users. A new system named NewsStand is presented that collects, analyzes, and displays news stories in a map interface, thus leveraging on their implicit geographic content. NewsStand monitors RSS feeds from thousands of online news sources and retrieves articles within minutes of publication. It then extracts geographic content from articles using a custombuilt geotagger, and groups articles into story clusters using a fast online clustering algorithm. By panning and zooming in NewsStand’s map interface, users can retrieve stories based on both topical significance and geographic region, and see substantially different stories depending on position and zoom level.
Point Labeling with Sliding Labels
 Computational Geometry: Theory and Applications
, 1999
"... This paper discusses algorithms for labeling sets of points in the plane, where labels are not restricted to some nite number of positions. We show that continuously sliding labels allows more points to be labeled both in theory and in practice. We dene six dierent models of labeling, and analyze ho ..."
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Cited by 50 (11 self)
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This paper discusses algorithms for labeling sets of points in the plane, where labels are not restricted to some nite number of positions. We show that continuously sliding labels allows more points to be labeled both in theory and in practice. We dene six dierent models of labeling, and analyze how much better  more points get a label  one model can be than another. We show that maximizing the number of labeled points is NPhard in the most general of the new models. Nevertheless, we give a polynomialtime approximation scheme and a simple and ecient factor 1 2 approximation algorithm for each of the new models. Finally, we give experimental results based on the factor 1 2 approximation algorithm to compare the models in practice. We also compare this algorithm experimentally to other algorithms suggested in the literature. 1 Introduction Annotating sets of points is a common task to be performed in Geographic Information Systems. Cities on smallscale maps are shown as...
A General Cartographic Labeling Algorithm
, 1996
"... Some apparently powerful algorithms for automatic label placement on maps use heuristics that capture considerable cartographic expertise but are hampered by provably inefficient methods of search and optimization. On the other hand, no approach to label placement that is based on an efficient optim ..."
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Cited by 48 (2 self)
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Some apparently powerful algorithms for automatic label placement on maps use heuristics that capture considerable cartographic expertise but are hampered by provably inefficient methods of search and optimization. On the other hand, no approach to label placement that is based on an efficient optimization technique has been applied to the production of general cartographic maps  those with labeled point, line, and area features  and shown to generate labelings of acceptable quality. We present an algorithm for label placement that achieves the twin goals of practical efficiency and high labeling quality by combining simple cartographic heuristics with effective stochastic optimization techniques. To appear in Cartographica. 1 Introduction Many apparently compelling techniques for automatic label placement use sophisticated heuristics for capturing cartographic knowledge, but, as noted by Zoraster (1991), also use inferior optimization strategies for finding good tradeoffs betwe...
A Survey of Automated Layout Techniques for Information Presentations
, 2001
"... Layout refers to the process of determining the sizes and positions of the visual objects that are part of an information presentation. Automated layout refers to the use of a computer program to automate either all or part of the layout process. This field of research lies at the crossroads between ..."
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Cited by 40 (3 self)
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Layout refers to the process of determining the sizes and positions of the visual objects that are part of an information presentation. Automated layout refers to the use of a computer program to automate either all or part of the layout process. This field of research lies at the crossroads between artificial intelligence and human computer interaction. Automated layout of presentations is becoming increasingly important as the amount of data that we need to present rapidly overtakes our ability to present it manually. We survey and analyze the techniques used by research systems that have automated layout components and suggest possible areas of future work.
Map Labeling and Its Generalizations
"... Map labeling is of fundamental importance in cartography and geographical information systems and is one of the areas targeted for research by the ACM Computational Geometry Impact Task Force. Previous work on map labeling has focused on the problem of placing maximal uniform, axisaligned, disjoint ..."
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Cited by 40 (5 self)
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Map labeling is of fundamental importance in cartography and geographical information systems and is one of the areas targeted for research by the ACM Computational Geometry Impact Task Force. Previous work on map labeling has focused on the problem of placing maximal uniform, axisaligned, disjoint rectangles on the plane so that each point feature to be labeled lies at the corner of one rectangle. Here, we consider a number of variants of the map labeling problem. We obtain three general types of results. First, we devise constantfactor polynomialtime approximation algorithms for labeling point features by rectangular labels, where the feature may lie anywhere on the boundary of its label region and where labeling rectangles may be placed in any orientation. These results generalize to the case of elliptical labels. Secondly, we consider the problem of labeling a map consisting of disjoint rectilinear line segments. We obtain constantfactor polynomialtime approximation algorithms for the general problem and an optimal algorithm for the special case where all segments are horizontal. Finally, we formulate a bicriteria version of the maplabeling problem and provide bicriteria polynomialtime approximation schemes for a number of such problems.
Label Layout for Interactive 3D Illustrations
 Journal of the WSCG
, 2005
"... Handmade illustrations in scientific and technical textbooks commonly use internal and external labels or legends to establish coreferential relation between pictorial elements and textual expressions. By analyzing the most complex examples, we extracted several label layout styles and classified ..."
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Cited by 33 (6 self)
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Handmade illustrations in scientific and technical textbooks commonly use internal and external labels or legends to establish coreferential relation between pictorial elements and textual expressions. By analyzing the most complex examples, we extracted several label layout styles and classified them. We propose a variety of realtime label layout algorithms that aim to produce nice and clean layouts. In order to achieve a framecoherent label layout during user interactions, the algorithms consider layout decisions from previous frame. Moreover, several evaluation criteria to measure the quality of static as well as dynamic label layouts are presented.