Agisoft Metashape

Agisoft Metashape => General => Topic started by: lolrider on March 17, 2014, 09:24:21 PM

Title: Importing georeferenced .obj model to Meshlab
Post by: lolrider on March 17, 2014, 09:24:21 PM

Hi,

I built a georeferenced and textured model in Photoscan, then imported it to Meshlab for further editing. But in Meshlab, model was broken and did not resemble the original one in any way. I used "EPSG::330" coordinate system. Then I tried "Local Coordinates" setting and Meshlab displayed the model correctly. So, the problem must be connected with georeferencing, I quess.
I tried the .ply format as well, but the problem was the same.

Any help and/or suggestions with this would be great.

Edo

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: stihl on March 17, 2014, 10:22:48 PM

Yep he looks dead, nice model!

Could you tell me what's keeping you from using local coordinates, as this model appears to be quite small so I personally see little use for a coordinate system.

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: lolrider on March 18, 2014, 12:28:03 AM

My plan is to view at least 10-20 georeferenced models at the same time. But in order to view them in the same position as they were in reality I need to georeference those models.
Viewing those models all together offers much more information than separately. At least in archeological terms.

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: Alexey Pasumansky on March 18, 2014, 01:03:30 AM

Hello Edo,

If using projected coordinate system, please use Shift fields for X and Y coordinates in Export model dialog to subtract large numbers from the vertices' coordinates.
Note that models with degrees as units will not be displayed properly in MeshLab due to different scale along X and Y axis.

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: mwillis on March 18, 2014, 01:38:24 AM

Are you using an arbitrary grid for your excavations?  Maybe you're using UTMs?  If UTMs, many software packages don't handle large numbers (like UTMs) well.  The normal way of dealing with this is removing the first couple of digits when you're placing your GCPs.  350,030 E 3,700,070 N would become 030 E 0070 N. Hope that makes sense.

Mark (another archaeologist...)

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: lolrider on March 19, 2014, 12:21:17 PM

I tried out both variants and they worked.

Thanks!

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: Diego ROn on March 19, 2014, 06:54:44 PM

Another way could be usign the new beta relese of meshlab that allows to use control points in txt fomat to allign meshes :) it's a cool tool... It works better if you avoid gegraphical coordinates, keep the topo data unreferenced (origin 0,0,0) and it will work quiet well ;)

Title: Re: Importing georeferenced .obj model to Meshlab
Post by: lolrider on March 21, 2014, 02:12:41 PM

Quote from: Diego ROn on March 19, 2014, 06:54:44 PM

Another way could be usign the new beta relese of meshlab that allows to use control points in txt fomat to allign meshes :) it's a cool tool... It works better if you avoid gegraphical coordinates, keep the topo data unreferenced (origin 0,0,0) and it will work quiet well ;)

Thanks for the tip. I will try it out, if I have time.