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jpeg to dxf

Muthuraman Chinnadurai

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Hello everyone,

I am trying to import an image in to my model however i am not clear on how to convert the .jpeg to .dxf, i tried a few online softwares but of no use. May your expertise assist me.

Thank you.

2 Replies Last Post 8 avr. 2013, 04:19 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 7 avr. 2013, 04:22 UTC−4
Hi

that is far from obvious, but there must be software out there that can do someting.

JPG are modulated bit maps, while DXF are vector coordinates, two different worlds.

COMSOL needs clasical geometry descritions, points, lines (linking two points), polylines (linked series of points and lines and closed polylines => surfaces, and closed surface => volumes This is a sub set of what DXF diles provide, as ther initially DXF stops at points and lines, and doesnt even have the polyline concept, "good CAD sofware" does present DXF sufficiently to give mostly coherehnt polylines hence can defined closed lins delimiting a flat surface, but it stops there. Other formats are required for 3D

So how to extract closed polylines from a bit map, even with a color or grey code per pixel ?
With contour lines is one way.

So far I have given up such conversions, as for my cases I have always fond a way to regenerate the geometry via a CAD software, but I know that medical images, porosity patterns as images from microscope or electron microscope can be converted even 3D cloud points can be reconstructed into meshed volumes.

Hopefully others out ther can come with some names, and I do believe one or more of the COMSOL associated companies have software compatible with such conversions, check their web sitze

--
Good luck
Ivar
Hi that is far from obvious, but there must be software out there that can do someting. JPG are modulated bit maps, while DXF are vector coordinates, two different worlds. COMSOL needs clasical geometry descritions, points, lines (linking two points), polylines (linked series of points and lines and closed polylines => surfaces, and closed surface => volumes This is a sub set of what DXF diles provide, as ther initially DXF stops at points and lines, and doesnt even have the polyline concept, "good CAD sofware" does present DXF sufficiently to give mostly coherehnt polylines hence can defined closed lins delimiting a flat surface, but it stops there. Other formats are required for 3D So how to extract closed polylines from a bit map, even with a color or grey code per pixel ? With contour lines is one way. So far I have given up such conversions, as for my cases I have always fond a way to regenerate the geometry via a CAD software, but I know that medical images, porosity patterns as images from microscope or electron microscope can be converted even 3D cloud points can be reconstructed into meshed volumes. Hopefully others out ther can come with some names, and I do believe one or more of the COMSOL associated companies have software compatible with such conversions, check their web sitze -- Good luck Ivar

Gunnar Andersson COMSOL Employee

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Posted: 1 decade ago 8 avr. 2013, 04:19 UTC−4
In some applications of images as sources of material data, you don't need an explicit representation of the geometry: You can import the image into Multiphysics as an Image function, define a geometry that represents the domain of the image data (typically a rectangle), and let the image function define the material property. You still have to mesh the geometry fine enough so that it resolves the gradients of the image sufficiently well.


In some applications of images as sources of material data, you don't need an explicit representation of the geometry: You can import the image into Multiphysics as an Image function, define a geometry that represents the domain of the image data (typically a rectangle), and let the image function define the material property. You still have to mesh the geometry fine enough so that it resolves the gradients of the image sufficiently well.