Build Orthomosaic 1.6.2 segmentation fault with imported DEM

[ashalota]

I'm importing a DEM from a .tif file. It looks good visually in the Ortho preview window area overlaid on the map, as expected. The 'no-data' area is showing as black. The chunk has 27 images in it, not a large area.

When I try to run build orthomosaic using it DEM as the source, it crashes in the GUI, and if trying to run this from python it shows this:

Code: [Select]

BuildOrthomosaic: projection = WGS 84 / UTM zone 19N, surface = DEM, blending mode = Mosaic, refine seamlines = 0, resolution = 0
initializing...
estimating tile boundaries... done in 25.7475 sec
generating 44591x35324 orthomosaic (10 levels, 0.0286791 resolution)
selected 26 cameras
saved orthomosaic data in 0.004399 sec
saved camera partition in 0.00308 sec
scheduled 2 orthophoto groups
loaded camera partition in 3.3e-05 sec
loaded orthomosaic data in 0.000608 sec
Orthorectifying 13 images
Segmentation fault
Any ideas? I want to load in my LiDAR derived DEMs in order to remove the distortion that is showing up in my orthomosaics, especially warping of buildings.

[Alexey Pasumansky]

Hello ashalota,

Which version of Metashape Pro you are using and what is the system configuration (OS version, CPU and available RAM)?

As for the no-data value, have you used the proper value during the import operation that corresponds to the no-data value from the external DEM file?

[ashalota]

Metashape Pro 1.6.2 build 10247 (64 bit)

OS = CentOS Linux 7 (Core)
CPU = Intel(R) Xeon(R) CPU E5-2695 v4 @ 2.10GHz 72
RAM = 750GB (i think)

[Alexey Pasumansky]

Hello ashalota,

Thank you for additional information. Would it be possible to send the DEM file that you are importing to support@agisoft.com, so that we could try to reproduce the problem on our side using similar configuration? If possible, please also provide the XML file with the camera locations (exported via File Menu -> Export Cameras option).

[ashalota]

Hi,

I sent that in to tech support but haven't heard back yet. Ticket #137052

[Alexey Pasumansky]

Hello ashalota,

We have examined the provided data and have found out that the source DEM has "nan" values for no-data areas. It causes the crashes, as in Metashape no-data is expected to be some existing value. In the next version update nan values will be ignored automatically on import. As for now, I can suggest to convert DEM in some external application and substitute nan values with some fixed number.