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Extracting topographic structure from digital elevation data for geographic information system analysis. Photogrammetric Engineering and Remote
 Sensing
, 1988
"... ABSTRACT: Software tools have been developed at the U.S. Geological Survey’s EROS Data Center to extract topographic structure and to delineate watersheds and overland flow paths from digital elevation models. The tools are special purpose FORTRAN programs interfaced with generalpurpose raster and ..."
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Cited by 196 (0 self)
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ABSTRACT: Software tools have been developed at the U.S. Geological Survey’s EROS Data Center to extract topographic structure and to delineate watersheds and overland flow paths from digital elevation models. The tools are special purpose FORTRAN programs interfaced with generalpurpose raster and vector spatial analysis and relational data base management packages. The first phase of analysis is a conditioning phase that generates three data sets: the original DEM with depressions filled, a data set indicating the flow direction for each cell, and a flow accumulation data set in which each cell receives a value equal to the number of cells that drain to it. The original DEM and these three derivative data sets can then be processed in a variety of ways to optionally delineate drainage networks, overland paths, watersheds for userspecified locations, subwatersheds for the major tributaries of a drainage network, or pour point linkages between watersheds. The computergenerated drainage lines and watershed polygons and the pour point linkage information can be transferred to vectorbased geographic information systems for further analysis. Comparisons between these computer generated features and their manually delineated counterparts generally show close agreement, indicating that these software tools will save analyst time spent in manual interpretation and digitizing.
A New Method For The Determination Of Flow Directions And Upslope Areas In Grid Digital Elevation Models
 Water Resources Research
, 1997
"... A new procedure for the representation of flow directions and calculation of upslope areas using rectangular grid digital elevation models is presented. The procedure is based on representing flow direction as a single angle taken as the steepest downwards slope on the eight triangular facets center ..."
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Cited by 114 (2 self)
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A new procedure for the representation of flow directions and calculation of upslope areas using rectangular grid digital elevation models is presented. The procedure is based on representing flow direction as a single angle taken as the steepest downwards slope on the eight triangular facets centered at each grid point. Upslope area is then calculated by proportioning flow between two downslope pixels according to how close this flow direction is to the direct angle to the downslope pixel. This procedure offers improvements over prior procedures that have restricted flow to eight possible directions (introducing grid bias) or proportioned flow according to slope (introducing unrealistic dispersion). The new procedure is more robust than prior procedures based on fitting local planes while retaining a simple grid based structure. Detailed algorithms are presented and results are demonstrated through test examples and application to digital elevation data sets. Introduction Flow direct...
Evaluation of Methods for Ridge and Valley Detection
 IEEE PAMI
, 1999
"... Abstract—Ridges and valleys are useful geometric features for image analysis. Different characterizations have been proposed to formalize the intuitive notion of ridge/valley. In this paper, we review their principal characterizations and propose a new one. Subsequently, we evaluate these characteri ..."
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Cited by 49 (3 self)
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Abstract—Ridges and valleys are useful geometric features for image analysis. Different characterizations have been proposed to formalize the intuitive notion of ridge/valley. In this paper, we review their principal characterizations and propose a new one. Subsequently, we evaluate these characterizations with respect to a list of desirable properties and their purpose in the context of representative image analysis tasks. Index Terms—Creases, separatrices, drainage patterns, comparative analysis. ————————— — F ——————————
I/OEfficient Algorithms for Problems on Gridbased Terrains (Extended Abstract)
 In Proc. Workshop on Algorithm Engineering and Experimentation
, 2000
"... Lars Arge Laura Toma Jeffrey Scott Vitter Center for Geometric Computing Department of Computer Science Duke University Durham, NC 277080129 Abstract The potential and use of Geographic Information Systems (GIS) is rapidly increasing due to the increasing availability of massive amoun ..."
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Cited by 33 (15 self)
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Lars Arge Laura Toma Jeffrey Scott Vitter Center for Geometric Computing Department of Computer Science Duke University Durham, NC 277080129 Abstract The potential and use of Geographic Information Systems (GIS) is rapidly increasing due to the increasing availability of massive amounts of geospatial data from projects like NASA's Mission to Planet Earth. However, the use of these massive datasets also exposes scalability problems with existing GIS algorithms. These scalability problems are mainly due to the fact that most GIS algorithms have been designed to minimize internal computation time, while I/O communication often is the bottleneck when processing massive amounts of data.
Drainage Queries in TINs: From local to global and back again
 In Proc. 7th Int. Symp. on Spatial Data Handling
, 1996
"... This paper considers the cost of preprocessing a digital terrain model (DTM) represented as a triangulated irregular network (TIN) so that drainage queriese.g., what is the watershed of a query point, or how much water passes through a point given that rain is falling at a known ratecan be ans ..."
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Cited by 27 (6 self)
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This paper considers the cost of preprocessing a digital terrain model (DTM) represented as a triangulated irregular network (TIN) so that drainage queriese.g., what is the watershed of a query point, or how much water passes through a point given that rain is falling at a known ratecan be answered by simply evaluating a summary function. Although the worstcase storage and preprocessing costs are high, the experimentallyobserved costs are reasonable. In order to compute a compact and consistent summary function, the drainage network needs a rigorous definition. This paper, therefore, also surveys some of the previous definitions, extends them, and establishes a number of properties of drainage networks with a focus on TINs. 1 Introduction Terrain drainage characteristics provide important information on water resources, possible flood areas, erosion and other natural processes. In natural resource management, for example, the basic management unit is the watershed, the area a...
On the effect of digital elevation model accuracy on hydrology and geomorphology
 Water Resources Research
, 1999
"... Abstract. This study compares published cartometric and photogrammetric digital elevation models (DEMs) of various grid spacings with a ground truth data set, obtained by ground survey, and studies the implications of these differences on key hydrologic statistics. Inferred catchment sizes and strea ..."
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Cited by 26 (0 self)
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Abstract. This study compares published cartometric and photogrammetric digital elevation models (DEMs) of various grid spacings with a ground truth data set, obtained by ground survey, and studies the implications of these differences on key hydrologic statistics. Inferred catchment sizes and stream networks from published DEMs were found to be significantly different than those from the ground truth in most instances. Furthermore, the width functions and cumulative area relationships determined from the published DEMs were found to fall consistently outside the 90 % confidence limits determined from the ground truth for more than 60 % of the relationship, suggesting that these hydrologic properties are poorly estimated from published DEMs. However, the slopearea relationships determined from published DEMs were found to be less sensitive to catchment shape, size, and stream network, with the relationship falling outside the 90 % confidence limits for less than 40 % of the relationship for all catchments identified from the published DEMs. A published relationship linking the horizontal resolution with the vertical accuracy of the DEM was tested, predicting a horizontal resolution of about 10 m for the published DEMs tested. 1.
2000: Multilocal creaseness based on the levelset extrinsic curvature. Computer Vision and Image Understanding 77(2
"... Creases are a type of ridge/valley structures of an image characterized by local conditions. As creases tend to be at the center of anisotropic greylevel shapes, creaseness can be considered a measure of medialness, and therefore as useful in many image analysis problems. Among the several possibil ..."
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Cited by 23 (8 self)
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Creases are a type of ridge/valley structures of an image characterized by local conditions. As creases tend to be at the center of anisotropic greylevel shapes, creaseness can be considered a measure of medialness, and therefore as useful in many image analysis problems. Among the several possibilities, a priori the creaseness based on the levelset extrinsic curvature (LSEC) is especially interesting due to its invariance properties. However, in practice, it produces a discontinuous response with a badly dynamic range. The same problems arise with other related creaseness measures proposed in the literature. In this paper, we argue that these problems are due to the very local definition of the LSEC. Therefore, rather than designing an ad hoc solution, we propose two new multilocal creaseness measures that we will show to be free of discontinuities and to have a meaningful dynamic range of response. Still, these measures are based on the LSEC idea, to preserve its invariance properties. We demonstrate the usefulness of the new creaseness measures in the context of two applications that we are currently developing in the field of 3D medical image analysis, the rigid registration of CT and MR head volumes and the orientation analysis of trabecular bone patterns. c ○ 2000 Academic Press Key Words: creases; curvature; divergence; structure tensor; trabecular bone; registration.
Terrain Analysis Using Digital Elevation Models in Hydrology
, 2003
"... This paper describes methods that use digital elevation models (DEMs) in hydrology, implemented as an ArcGIS toolbar using Visual Basic and the ESRI object library. I describe generalized channel network delineation to objectively estimate drainage density and by using terrain curvature accommodate ..."
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Cited by 21 (1 self)
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This paper describes methods that use digital elevation models (DEMs) in hydrology, implemented as an ArcGIS toolbar using Visual Basic and the ESRI object library. I describe generalized channel network delineation to objectively estimate drainage density and by using terrain curvature accommodate spatially variable drainage density. The multiple flow direction field determined from a DEM also serves as a basis for routing overland and topographically driven subsurface flow useful in water quality, erosion and terrain stability modeling. New DEM derived quantities, such as downslope influence, upslope dependence, decayed accumulation, downslope accumulation and transport limited accumulation are illustrated.
Advances in the mapping of flow networks from digital elevation data
 World Water and Environmental Resources Congress
, 2001
"... Digital elevation models (DEMs) are a useful data source for the automatic delineation of flow paths, sub watersheds and flow networks for hydrologic modeling. Digital representation of the flow network is central to distributed hydrologic models because it encodes the model element linkages through ..."
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Cited by 19 (5 self)
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Digital elevation models (DEMs) are a useful data source for the automatic delineation of flow paths, sub watersheds and flow networks for hydrologic modeling. Digital representation of the flow network is central to distributed hydrologic models because it encodes the model element linkages through which flow is routed to the outlet. The scale (drainage density) of the flow network, used controls the scale of hillslope and channel model elements. Although field mapping is acknowledged as the most accurate way to determine channel networks and drainage density, it is often impractical, especially for large watersheds, and DEM derived flow networks then provide a useful surrogate for channel or valley networks. There are a variety of approaches to delineating flow networks, using different algorithms such as single (drainage to a single neighboring cell) and multiple (partitioning of flow between multiple neighboring cells) flow direction methods for the computation of contributing area and local identification of upwards curvature. The scale of the delineated network is sometimes controlled by a support area threshold, which may impose an arbitrary and spatially constant drainage density. This paper examines methods for the delineation of flow networks using grid DEMs. We examine the question of objective estimation of drainage density and describe a method based on terrain curvature that can accommodate spatially variable drainage density. The methods presented have been incorporated as a component of the TMDL Toolkit software developed to support hydrologic and water quality modeling and available from
TerraStream: From elevation data to watershed hierarchies
 Proc. ACM Sympos. on Advances in Geographic Information Systems
"... We consider the problem of extracting a river network and a watershed hierarchy from a terrain given as a set of irregularly spaced points. We describe TerraStream, a “pipelined ” solution that consists of four main stages: construction of a digital elevation model (DEM), hydrological conditioning, ..."
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Cited by 19 (10 self)
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We consider the problem of extracting a river network and a watershed hierarchy from a terrain given as a set of irregularly spaced points. We describe TerraStream, a “pipelined ” solution that consists of four main stages: construction of a digital elevation model (DEM), hydrological conditioning, extraction of river networks, and construction of a watershed hierarchy. Our approach has several advantages over existing methods. First, we design and implement the pipeline so each stage is scalable to massive data sets; a single nonscalable stage would create a bottleneck and limit overall scalability. Second, we develop the algorithms in a general framework so that they work for both TIN and grid DEMs. TerraStream is flexible and allows users to choose from various models and parameters, yet our pipeline is designed to reduce (or eliminate) the need for manual intervention between stages. We have implemented TerraStream and present experimental results on real elevation point sets that show that our approach handles massive multigigabyte terrain data sets. For example, we can process a data set containing over 300 million points—over 20GB of raw data—in under 26 hours, where most of the time (76%) is spent in the initial CPUintensive DEM construction stage. 1