Rank: 52 based on 689 downloads (last 30 days) and 13 files submitted
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David Legland

E-mail
Company/University
INRA, France

Personal Profile:

Research engineer in Image processing.

Interested in image registration problems, estimation in discrete images, and polyhedral reconstruction.

web page:
http://www.pfl-cepia.inra.fr/ (in french)
See also:
http://matgeom.sourceforge.net

Professional Interests:
image analysis, applied statistics, geometric computing, registration

 

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Files Posted by David View all
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Updated   File Tags Downloads
(last 30 days) 		Comments Rating
16 May 2012 Screenshot Image chamfer distances and geodesic diameter Propagates geodesic distances in binary images, and compute geodesic diameter Author: David Legland image, distance, geodesic, chamfer, image processing 24 0
05 Apr 2012 Screenshot geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland geometry, 3d, geometric computing, polygon, plane, polyhedron 276 25
  • 5.0
5.0 | 12 ratings
29 Feb 2012 Screenshot geom2d Geometry library for matlab. Performs geometric computations on points, lines, circles, polygons... Author: David Legland mathematics, plan, display, intersection, polygon, computational geometr... 179 40
  • 3.78571
3.8 | 17 ratings
07 Dec 2011 Screenshot image ellipsoid 3D Inertia ellipsoid of a 3D grayscale image Author: David Legland ellipsoid, image processing, inertia, image analysis 13 0
09 Nov 2011 geometric measures in 2D/3D images Measure of geometric parameters in 2D or 3D images (surface, perimeter, Euler Number...) Author: David Legland image analysis, particle analysis, region properties, minkowski functionals, intrinsic volumes, geometric measures 52 3
  • 5.0
5.0 | 1 rating
Comments and Ratings by David View all
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Updated File Comments Rating
15 May 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland

Hi Amanda,
I do not know similar library for scilab. I suspect you need to re-code everything...
If you are looking for a free alternative, I can mention a port to octave of libraries geom3d+geom2d:
http://octave.sourceforge.net/geometry/index.html

regards,
David
08 Mar 2012 geom2d Geometry library for matlab. Performs geometric computations on points, lines, circles, polygons... Author: David Legland

Hi sumitha,
basic format for representing lines is [x0 y0 dx dy], where (w0,y0) refers to origin point, and (dx,dy) to direction vector. You can create a line orthogonal to direction THETA with:
 line1 = [x0 Y0 -sin(THETA) cos(THETA)];
 drawLine(line1);
Regards.
03 Mar 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland

Hi Nir,
did you mean 3D polygon or 3D mesh ? It seems you speak about mesh, right ? In this case you case use function "intersectLineMesh" (contained in the updated submission). This should do the job.

@Benjamin: I have also added a function polygonArea3d in the update.
01 Mar 2012 geom2d Geometry library for matlab. Performs geometric computations on points, lines, circles, polygons... Author: David Legland

Hi Benjamin, the clipping of polygon is not an easy problem. There are efficient algorithms, and their inclusion is planned, but I still haven't found time to write them down. It seems the mapping toolbox provides facilities for this, maybe you can check it.
Regards, David
24 Feb 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland

Hi Ben,

you can check the function "polyhedronSlice". It computes the 3D polygon that results from the intersection of a polyhedron with a plane. Example of use:
 [nodes faces] = createCube;
 plane = createPlane([.5 .5 .5], [2 3 4]);
 poly = polyhedronSlice(nodes, faces, plane);
 figure; hold on;
 drawMesh(nodes, faces, 'facealpha', .5);
 fillPolygon3d(poly, 'm');

There is no (not yet...) function for computing area of a 3D polygon. However it can be obtained by projecting on the intersecting plane:
 poly2d = planePosition(poly, plane);
 area = abs(polygonArea(poly2d))

Regards, David
Comments and Ratings on David's Files View all
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Updated File Comment by Comments Rating
21 May 2012 Region Adjacency Graph (RAG) Computes the graph of adjacent regions in a labeled image Author: David Legland Chen
15 May 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland Legland, David

Hi Amanda,
I do not know similar library for scilab. I suspect you need to re-code everything...
If you are looking for a free alternative, I can mention a port to octave of libraries geom3d+geom2d:
http://octave.sourceforge.net/geometry/index.html

regards,
David
11 May 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland Amanda

Hi, David
Having been using this package for years. Really love it. Thanks for your gr8 job. Now I'm researching using Scilab to replace Matlab for some application. Searched scilab but didn't find geom3d available there. Any suggestion?
11 May 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland Amanda
10 May 2012 geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland Tianjin Univ
Top Tags Applied by David
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image processing, display, image, 3d, computational geometry
Files Tagged by David View all
  • 1 - 5 of
  • 14
Updated   File Tags Downloads
(last 30 days) 		Comments Rating
16 May 2012 Screenshot Image chamfer distances and geodesic diameter Propagates geodesic distances in binary images, and compute geodesic diameter Author: David Legland image, distance, geodesic, chamfer, image processing 24 0
05 Apr 2012 Screenshot geom3d Library to handle 3D geometric primitives: create, intersect, display, and make basic computations Author: David Legland geometry, 3d, geometric computing, polygon, plane, polyhedron 276 25
  • 5.0
5.0 | 12 ratings
29 Feb 2012 Screenshot geom2d Geometry library for matlab. Performs geometric computations on points, lines, circles, polygons... Author: David Legland mathematics, plan, display, intersection, polygon, computational geometr... 179 40
  • 3.78571
3.8 | 17 ratings
07 Dec 2011 Screenshot image ellipsoid 3D Inertia ellipsoid of a 3D grayscale image Author: David Legland ellipsoid, image processing, inertia, image analysis 13 0
09 Nov 2011 geometric measures in 2D/3D images Measure of geometric parameters in 2D or 3D images (surface, perimeter, Euler Number...) Author: David Legland image analysis, particle analysis, region properties, minkowski functionals, intrinsic volumes, geometric measures 52 3
  • 5.0
5.0 | 1 rating

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