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Filtering with raster signatures

Leonardo Guerreiro Azevedo, Ralf Hartmut Güting, Rafael Brand Rodrigues, Geraldo Zimbrão, Jano Moreira de Souza
2006 Proceedings of the 14th annual ACM international symposium on Advances in geographic information systems - GIS '06  
This work proposes a new raster approximation (Three-Color Raster Signature -3CRS) for representing different data types (polygons, polylines and points), and to be used as filter in the second step of  ...  However, the exact intersection test of two spatial objects is the most timeconsuming and I/O-consuming step in processing spatial joins.  ...  there are some proposals for processing polylines × polylines joins and polygon × polyline joins.  ... 
doi:10.1145/1183471.1183503 dblp:conf/gis/AzevedoGRZS06 fatcat:qd4yogmjyjgyndwrm3axrwhhnq

Building a scaleable geo-spatial DBMS

Jignesh Patel, Curt Ellmann, Jim Kupsch, Shelly Guo, Johan Larson, David De Witt, Jeffrey Naughton, JieBing Yu, Navin Kabra, Kristin Tufte, Biswadeep Nag, Josef Burger (+3 others)
1997 Proceedings of the 1997 ACM SIGMOD international conference on Management of data - SIGMOD '97  
This paper presents a number of new techniques for parallelizing geo-spatial database systems and discusses their implementation in the Paradise object-relational database system.  ...  The effectiveness of these techniques is demonstrated using a variety of complex geo-spatial queries over a 120 GB global geo-spatial data set.  ...  Olsen at NASA Goddard for her assistance in helping us acquire the AVHRR data sets used in this benchmark.  ... 
doi:10.1145/253260.253342 dblp:conf/sigmod/PatelYKTNBHRLEKGDN97 fatcat:ftg2gdjh5jfdzb6t6nrqp7wzlm

Large-scale spatial data processing on GPUs and GPU-accelerated clusters

Jianting Zhang, Simin You, Le Gruenwald
2015 SIGSPATIAL Special  
In this article, we report our works on data parallel designs of spatial indexing, spatial joins and several other spatial operations, including polygon rasterization, polygon decomposition and point interpolation  ...  In addition to introducing GPGPU computing background and outlining data parallel designs for spatial operations, references to individual works are provided as a summary chart for interested readers to  ...  We have also developed a GPU-based spatial join framework to join two indexed spatial datasets based on point-in-polygon tests [18] , point-to-polyline distance [26] , polyline-to-polyline similarity  ... 
doi:10.1145/2766196.2766201 fatcat:263nzf6ojbhqnaruvovsxqqog4

Weighted Visibility Classification and Seating Plan for the Aitken University Centre

T. Allison, D. Fraser, E. Stefanakis
2014 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
This paper describes the requirements for a weighted visibility classification of seats in the University of New Brunswick's (UNB) Aitken University Centre (AUC).  ...  The visibility calculations compute the number of visible pixels of the rink surface for each seat. It is expected that seats with a higher number of visible pixels will also have better visibility.  ...  To facilitate the process of selecting all the seat from a single, a polyline was drawn around the rink intersecting all the seats in the given row.  ... 
doi:10.5194/isprsarchives-xl-2-227-2014 fatcat:zemwbtplsraofc4m3guqq3arxm

Automatic reconstruction of skeletal structures from TLS forest scenes

A. Schilling, H.-G. Maas
2014 ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
<br><br> For this reason, we propose a strategy to obtain skeletal structures of trees from single scans following a divide-and-conquer approach well-known from computer science.  ...  Second, each component is processed separately: A 2D skeleton is obtained via the Voronoi Diagram and refined.  ...  The result is a compact representation of the subset's point distribution as a 3D polygonal line (polyline for short), since the relation of 2D raster coordinates to 3D coordinates is known as stated in  ... 
doi:10.5194/isprsannals-ii-5-321-2014 fatcat:5lndh5ejnza3zeikneh4qhcdom

Symbol spotting in vectorized technical drawings through a lookup table of region strings

Marçal Rusiñol, Josep Lladós, Gemma Sánchez
2009 Pattern Analysis and Applications  
It has been proved to work even in the presence of noise and distortion introduced by the scanning and raster-to-vector processes.  ...  A voting scheme formulates hypothesis in certain locations of the line drawing image where there is a high presence of regions similar to the queried ones, and therefore, a high probability to find the  ...  Sánchez for proofreading the manuscript.  ... 
doi:10.1007/s10044-009-0161-2 fatcat:7psneqydpnfwrl7bilrxxfcr7e

A survey of non-thinning based vectorization methods [chapter]

Liu Wenyin, Dov Dori
1998 Lecture Notes in Computer Science  
The purpose of the survey is to provide researchers with a comprehensive overview of this technique for them to choose a suitable method when developing their vectorization algorithms and systems.  ...  We survey the methods developed up to date for crude vectorization of document images.  ...  Introduction Vectorization, also known as raster to vector conversion, is a process that finds the vector lines from the raster images.  ... 
doi:10.1007/bfb0033241 fatcat:76arsrgscjc3njopgmiqr3t4dm

From Raster to Vectors: Extracting Visual Information from Line Drawings

Liu Wenyin, Dov Dori
1999 Pattern Analysis and Applications  
The purpose of the survey is to provide researchers with a comprehensive overview of this technique, to enable a judicious decision while selecting a vectorisation algorithm for a system under development  ...  Vectorisation of raster line images is a relatively mature subject in the document analysis and recognition field, but it is far from being perfect as yet.  ...  INTRODUCTION Vectorisation, also known as raster to vector conversion, is a process that finds the vectors -straight line segmentsfrom the raster images.  ... 
doi:10.1007/s100440050010 fatcat:rrvdqkumofef5i6nwqcbneqrx4


Ayman Mohamed Assem
2019 JES. Journal of Engineering Sciences  
Repeating the process of functional evaluation after receiving feedbacks from the clients is one of the main disadvantages of the traditional method, and could consume more time to reproduce calculation  ...  for area calculations and visual presentation.  ...  based on a predefined criterion Extracting GIS raster features that generate coloured illustrations After creating the colored layers, the used layers for presentation could be converted to a raster  ... 
doi:10.21608/jesaun.2019.115757 fatcat:v4ous4birjfc7gp2v65ue4nsjm

Real-time Photorealistic Visualisation of Large-scaleMultiresolution Terrain Models

Anupam Agrawal, R.C. Joshi, M. Radhakrishna
2007 Defence Science Journal  
This paper describes a novel approach for objects and terrain visualisation by combination of two algorithms, one for terrain data and the other for objects.  ...  A polygonal model of very large terrain data requires a large number of triangles.  ...  It displays the 2-D scanned topographic map or raster image in the background. A user may select the vector digitisation option and capture a linear feature as collection of 2-D points on a polyline.  ... 
doi:10.14429/dsj.57.1742 fatcat:greuecis7rgdhfk34utqqcntku

Sparse pixel vectorization: an algorithm and its performance evaluation

D. Dori, Wenyin Liu
1999 IEEE Transactions on Pattern Analysis and Machine Intelligence  
Accurate and efficient vectorization of line drawings is essential for their higher level processing. We present a thinningless Sparse Pixel Vectorization (SPV) algorithm.  ...  The result is a crude polyline, which is refined through polygonal approximation by removing redundant points.  ...  A raster image, in contrast, conveys less semantics and requires much more space to store a large amount of pixels for the purpose of describing the same graphic object.  ... 
doi:10.1109/34.754586 fatcat:cywcpp5e4vfq7fg5wjjbdkawoi

The Berytus-Heliopolis Baalbak Road In The Roman Period: A Least Cost Path Analysis

Georges Abou Diwan, Jean Doumit
2017 Zenodo  
During the Roman period, official authorities were confronted to a significant challenge in establishing an efficient route joining the colony of Berytus to its territorial possessions in the northern  ...  Bekaa which included the town of Heliopolis Baalbak.  ...  The path was then converted to a polyline using The Raster to Polyline Conversion tool (Fig. 4) .  ... 
doi:10.5281/zenodo.1005582 fatcat:xpearrqzcvdlpls4qj6jhplaae

Ad hocmatching of vectorial road networks

E. Safra, Y. Kanza, Y. Sagiv, Y. Doytsher
2013 International Journal of Geographical Information Science  
This paper presents algorithms for ad hoc integration of maps in which roads are represented as polylines.  ...  The main novelty of these algorithms is in using only the locations of the endpoints of the polylines rather than trying to match whole lines.  ...  The output is an approximate matching of the polylines. Computing the matching is a three-step process.  ... 
doi:10.1080/13658816.2012.667104 fatcat:ey4oevz2t5eg3lp2mdkrqr6nby

Incremental arc segmentation algorithm and its evaluation

L. Wenyin, D. Dori
1998 IEEE Transactions on Pattern Analysis and Machine Intelligence  
Parts of six real drawings, containing about 200 arcs, are also processed. The algorithm works well for arc segments greater than 10 pixels in radius, π/4 in angle, and one pixel in width.  ...  We present an incremental arc segmentation algorithm, which recovers the vectorized arc fragments obtained by the vectorization of a piece of arc image in a stepwise fashion.  ...  We first construct PB 0 , the PB of the segment joining the two endpoints of the polyline.  ... 
doi:10.1109/34.677280 fatcat:2o2wllethfhnpbnjfky2t4s2ym

Automatic Methods for Disambiguating Author Names in Bibliographic Data Repositories

Anderson A. Ferreira, Marcos André Gonçalves, Alberto H.F. Laender
2015 Proceedings of the 15th ACM/IEEE-CE on Joint Conference on Digital Libraries - JCDL '15  
Monte-carlo techniques for falsification of temporal properties of non-linear hybrid systems. HSCC, 2010. c 4 (r 17 ) William R.  ...  Bhattacharya, (r 3 ) A. Gupta, (r 4 ) A. Verma. Building reusable dictionary repositories for real-world text mining.  ...  Estolano, F Neto A multi-user key and data exchange protocol to manage a secure database A raster approximation for processing of polyline joins xv simposio brasileiro de banco de dados xviii  ... 
doi:10.1145/2756406.2756930 dblp:conf/jcdl/FerreiraGL15 fatcat:hcrs42ciobhdvokzgnropm5dhe
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