DEM Generation - Bad Allocation

[Emma]

Hi everyone,

I'm having a bit of trouble building my DEM.

I've created a dense point cloud from 112 images, resulting in 23 million points. When I go to create a DEM (geographic option), I get the Not Enough Memory/Bad Allocation error. I've read a few post about this but not been able to find a solution.

My computer has 32GB RAM and I've built DEMs this way before with no problems at all, so I'm not sure what the problem is.

Anyone got an idea?

Thanks!

[Alexey Pasumansky]

Hello Emma,

Can you provide the processing log from the Console pane related to the failed operation?

I assume that the problem could be related to incorrect georeferencing that causes abnormal DEM size.

[Emma]

Hi Alexey,

Here's the console:

2019-07-09 16:13:54 Loading project...
2019-07-09 16:13:54 loaded project in 0.798 sec
2019-07-09 16:13:54 Finished processing in 0.798 sec (exit code 1)
2019-07-09 16:14:02 Finished processing in 0 sec (exit code 1)
2019-07-09 16:14:05 BuildDem: projection = GDA2020 / MGA zone 55, source data = Dense cloud, interpolation = Enabled, resolution = 0.0010332
2019-07-09 16:14:05 Generating DEM...
2019-07-09 16:14:05 initializing...
2019-07-09 16:14:05 generating 1348321x19362288093 dem (10 levels, 0.0010332 resolution)
2019-07-09 16:14:05 saved elevation data in 0.027 sec
2019-07-09 16:15:15 Finished processing in 69.975 sec (exit code 0)
2019-07-09 16:15:15 Error: bad allocation
>>>

The georeferencing should be fine, as I did it exactly the same way as I've done before with no issues building the DEM.

Thanks!

[Alexey Pasumansky]

Hello Emma,

The dimensions of 1,348,321 x 19,362,288,093 pixels and 1mm resolution doesn't seem to be correct. It means that the area of reconstruction is 1.5 x 20 000 km - it is several times longer than Australia dimensions.

Are you using imported dense cloud as a source or it is the result of processing in Metashape? In the latter case, can you please send the PSZ project with the alignment results and referencing information only to support@agisoft.com?

[Emma]

Hi Alexey,

I've just realised that I should be using GDA94 not GDA2020. I'm rebuilding the model and I'll see how that goes!

I'll send the PSZ file through if I still get the same problem.

Thanks!

[Alexey Pasumansky]

The problem was related to the insufficient referencing data. Including three markers in georeferencing operation (check the markers in the Reference pane and press Update button) solved the problem.