Difficulté à convertir un fichier raster en CAD

Question

<\/HEAD>Je suis étudiant et je travaille sur un projet scolaire, mais je ne connais pas le logiciel ArcGIS. Je dois réaliser un plan de nivellement sur un site, et pour cela, je dois transférer un raster contenant des données d'élévation dans AutoCAD. Le type de fichier actuel est OVR et je dois convertir ce fichier en AutoCAD sans perdre aucune donnée d'élévation. Toute aide serait grandement appréciée.<\/P><\/BODY><\/HTML>

XanderBakker · Answer

I have done this for a project some time ago (20+ years ago!). What we did was create a hillshade and mix it with the elevation colors and export as TIF and use it as background in AutoCAD.

Now, before you go there, do you really need to do this in CAD? Remember that you can bring your CAD data into ArcGIS and create some beautiful cartography in ArcGIS too.

Cody Benkelman · Answer

Cameron

the *.ovr file is a reduced resolution view ("overview" or "pyramid") of an original file - you may want to double check in the folder (if you got it?) to see if there's a *.tif or other file with the same basename.  The *.ovr file will be smaller in size but not the full resolution of the original - not sure if that matters (but I wonder why you were given the *.ovr instead of the original).

But that is somewhat academic, hoping to inform you.  For a quick answer to your immediate need:  try making a copy and changing the extension to *.tif.  The *.ovr format is fundamentally tiff inside and this may simply work, although I expect the *.ovr will contain multiple resolutions within it, and I don't know for certain if Autocad will handle it properly.

If the above does not work and you have ArcGIS, try reading the *.ovr --> renamed .tif by loading it into the map.  If it appears black, apply a stretch to see if you have good elevation values.  Let us know if any of these instructions are too sparse.  also let us know if you have ArcMap or ArcGIS Pro, and what version.  Sorry I won't be any help with AutoCAD.

Cody B.

DanPatterson_Retired · Answer

Raster to Polyline .... but absolutely no guarantee that the attributes will be carried forward since I suspect the *.ovr file is merely a picture and you might have to ascribe the numeric values to any resultant polylines after the fact.  I wouldn't even be able to suggest a workflow that was simple if that was the case