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Region representation: quadtrees from boundary codes

Hanan Samet
1980 Communications of the ACM  
Samet , Region represeul ta t i o n : boundary codes from quadtrees.  ...  description of a simply-connected region 's boundary into a quadtree representation of the region .  ... 
doi:10.1145/358826.358836 fatcat:h3al52e3kjb63m56xc4qb3gco4

Region representation: boundary codes from quadtrees

Charles R. Dyer, Azriel Rosenfeld, Hanan Samet
1980 Communications of the ACM  
doi:10.1145/358826.358838 fatcat:i2yvnc3lyffh5gtndnsgcdxkhq

Color LAR Codec: A Color Image Representation and Compression Scheme Based on Local Resolution Adjustment and Self-Extracting Region Representation

O. Deforges, M. Babel, L. Bedat, J. Ronsin
2007 IEEE transactions on circuits and systems for video technology (Print)  
Index Terms-Scalable coding, Gray-level and color images segmentation, Region representation based coding, Region of Interest Coding.  ...  More precisely, the segmentation process can be simultaneously performed at both the coder and the decoder from only the luminance component highly compressed by the first coding layer.  ...  The direct rebuilding of regions from block representation ensures compatibility between shape and region content.  ... 
doi:10.1109/tcsvt.2007.897112 fatcat:fb5afnyvf5gvhktbcwk6xihtku

A polygon soup representation for multiview coding

T. Colleu, S. Pateux, L. Morin, C. Labit
2010 Journal of Visual Communication and Image Representation  
The representation is extracted from MVD data in two steps. First, a set of 3D quads is extracted thanks to quadtree decomposition performed on depth maps.  ...  Moreover, the proposed methodology for extracting the representation allows to reduce ghosting artifacts. Finally, an adapted compression technique is proposed that limits coding artifacts.  ...  On the contrary, the quad based example does not contain such artifacts because the quadTree structure allows to code foreground and background regions separately. • The quad-based approach does not contain  ... 
doi:10.1016/j.jvcir.2010.01.003 fatcat:x3isiu7snfeyjmkufvvtgmwv4i

A consistent hierarchical representation for vector data

Randal C. Nelson, Hanan Samet
1986 Proceedings of the 13th annual conference on Computer graphics and interactive techniques - SIGGRAPH '86  
A C o n s i s t e n t H i e r a r c h i c a l R e p r e s e n t a t i o n f o r V e c t o r D a t a Abstract: A consistent hierarchical data structure for the representation of vector data is presented  ...  We have benefited greatly from discussions with Clifford A. Shaffer and Robert E. Webber.  ...  The Line Quadtree The line quadtree [Same84a] is also based on the region quadtree, and represents curvcs by the boundaries of the encoded regions.  ... 
doi:10.1145/15922.15908 dblp:conf/siggraph/NelsonS86 fatcat:2gk3b6id3vdpdp5agfcprln4cm

Recursive Representation and Progressive Display of Binary Objects for Efficient Network Browsing

I-Pin Chen, Zen Chen
1998 Journal of Visual Communication and Image Representation  
Our method determines the color coding methods apply a set of basis images, each with a of a quadtree node based on the (angle, intercept) representation different block structure ranging from a low spatial  ...  approximated are commonly used: quadtree representation [1, 2, 3] and by a shape of a polygon can be represented as a collection transform coding [18] .  ...  object is subject to line information, compared to the quadtree representation method using a region-based representation.  ... 
doi:10.1006/jvci.1998.0401 fatcat:hryf7xuij5hptkzspdasmmof2y

Hierarchical representations of collections of small rectangles

Hanan Samet
1988 ACM Computing Surveys  
The other representation is area based-that is, it depends on the physical extent of each rectangle.  ...  In this case, one representation reduces each rectangle to a point in a higher multidimensional space and treats the problem as one involving point data.  ...  ACKNOWLEDGMENTS I have benefitted greatly from many discussions with Mike Dillencourt as this paper was written.  ... 
doi:10.1145/50020.50021 fatcat:l66m7opx2zgsbcjbt3wylw7atq

Using topological sweep to extract the boundaries of regions in maps represented by region quadtrees

M. B. Dillencourt, H. Samet
1996 Algorithmica  
A variant of the plane-sweep paradigm known as topological sweep is adapted to solve geometric problems involving two-dimensional regions when the underlying representation is a region quadtree.  ...  The algorithm works for many different quadtree representations including those where the quadtree is stored in external storage.  ...  Of course, other representations of the boundary (e.g., chain codes [12] ) are also possible, and the algorithms of this paper can be readily adapted to produce them.  ... 
doi:10.1007/bf01942608 fatcat:52ejo35uprabrhvxxeus2ojfkm

Multiresolution Surface and Volume Representations [chapter]

Oliver G. Staadt
2004 Mathematics and Visualization  
We present a wavelet-based geometry compression pipeline in the context of hierarchical surface and volume representations.  ...  Two geometry simplification schemes, which are able to build hierarchical mesh representations, are an essential part of the pipeline.  ...  Once the tree is built from the above procedure, the quadtree cells have to be triangulated.  ... 
doi:10.1007/978-3-662-07443-5_23 fatcat:fvmmmpeexbfdzjhva3kuj356ma

Compact quad-based representation for 3D video

T. Colleu, L. Morin, C. Labit, S. Pateux, R. Balter
2009 2009 3DTV Conference: The True Vision - Capture, Transmission and Display of 3D Video  
Index Terms-3D video, data representation, multiview video plus depth, quadtree, 3D quads, compression.  ...  The representation is obtained into two steps. Firstly, a set of 3D quads is extracted by using a quadtree decomposition of the depth maps.  ...  Then, the coding method of this representation must be studied in order to enhance the compactness of the representation.  ... 
doi:10.1109/3dtv.2009.5069648 fatcat:fyemmhw3yzaevo5u5jdqr5orta

Image Segmentation with Topological Maps and Inter-pixel Representation

Jean-Pierre Braquelaire, Luc Brun
1998 Journal of Visual Communication and Image Representation  
In that case the recognition of objects from regions is done in latter stages.  ...  Find the boundary element shared by two regions or the two regions sharing a same boundary element. 5.  ...  Moreover we have seen that the inter-pixel boundary representation provides a geometrical representation of segmented images which is consistent from a topological point of view.  ... 
doi:10.1006/jvci.1998.0374 fatcat:fku6uhal2rckbafywcz3mmzkqm

Multiresolution Mesh Representation: Models and Data Structures [chapter]

Leila De Floriani, Paola Magillo
2002 Mathematics and Visualization  
Multiresolution meshes are a common basis for building representations of a geometric shape at different levels of detail.  ...  A multiresolution mesh provides several alternative meshbased approximations of a spatial object (e.g., a surface describing the boundary of a solid object, or the graph of a scalar field).  ...  MINGLE -Multiresolution in Geometric Modelling", contract number HPRN-CT-1999-00117, and by the National Project founded by the Italian Ministry of Instruction, University and Research (MIUR) "SPADA -Representation  ... 
doi:10.1007/978-3-662-04388-2_13 fatcat:w6wtws7fabbcdmfxd6lvayvgxq

A new region expansion for quadtrees

C.-H. Ang, H. Samet, C.A. Shaffer
1990 IEEE Transactions on Pattern Analysis and Machine Intelligence  
A one-pass algorithm is presented to perform region expansion in images that are represented by quadtrees.  ...  In such a case, a pointer-based representation may require many disk pages to be accessed. Thus alternative representations such as the linear quadtree [3] , [ I ] are used.  ...  Each leaf node is represented by its locational code which corresponds to a sequence of directional codes that locate the leaf along a path from the root of the tree.  ... 
doi:10.1109/34.56221 fatcat:45rztgzarjeihng2ifpsnp4q74

Large mesh generation from boundary models with parametric face representation

Reinhard Klein, Wolfgang Straber
1995 Proceedings of the third ACM symposium on Solid modeling and applications - SMA '95  
The triangulation of boundary representation geometries (BRep geometries) is neccessary for display generation, stereo-lithography applications and also finite element mesh (FE mesh) generation.  ...  Another advantage of the algorithm is that the error between the linear approximation of the boundary and the boundary itself is controlled step by step until it lies within a predefined tolerance : Because  ...  Shimada and Gossard generate adaptive 2D/3D meshes for a given boundary representation of the geometry of a space region and a density distribution over that region.  ... 
doi:10.1145/218013.218097 dblp:conf/sma/KleinS95 fatcat:5sbgllvptjcanhyguolztsegha

Region-based fractal image compression

H. Hartenstein, M. Ruhl, D. Saupe
2000 IEEE Transactions on Image Processing  
In this paper we present a fractal coder that derives highly image-adaptive partitions and corresponding fractal codes in a time-efficient manner using a region-merging approach.  ...  Index Terms-Fractal compression, image compression, image partitions, segmentation-based coding.  ...  We have focused on two different methods to encode the configuration of range boundaries: chain codes and region edge maps.  ... 
doi:10.1109/83.847831 pmid:18262956 fatcat:hw635xzzkrb5lgczmvhw5j5r5m
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