"Can't build model" when trying to Build Geometry

[jan]

Hello,

I want to make a low quality model from 175 pictures, as I want to have it fast to have a preview.

the pictures were aligned well in low quality mode. However when executing the "Build Geometry..." step, PhotoScan immediately comes with a tiny pop-up window that says: "Can't build model".
The camera positions are displayed above the point cloud, and they seem to be correct. However in the cameras panel, all camera coordinates are all 0.

I'm using PhotoScan 0.9.0 build 1586


What could be wrong?

[Alexey Pasumansky]

Hello Jan,

If you do not have any valid coordinates for cameras all camera instances should be unchecked in the Ground Control pane.

Please also check if there are any messages in the Console pane when you try to create geometry - probably some images are missing or paths are incorrect.
The other possible reason is incorrect Bounding Box position - it should contain the area of reconstruction with sparse point cloud.

[jan]

Hello Alexey,

I do not have a priori camera position. However after alignment, photoscan seems to reconstruct these camera coordinates correctly.

All camera instances are unchecked in the ground control pane.
The bounding box contains the point cloud and also the by Photoscan calculated camera positions.

Below is the text generated by the console, when trying to build geometry (after this a pop-up appears saying 'Can't build model'):

Using device: GeForce GTX 580, 16 compute units, 1503 MB global memory
  max work group size 1024
  max work item sizes [1024, 1024, 64]
  max mem alloc size 375 MB
  max workgroup size c1: 1024 c3: 1024 zero: 1024 hamming: 1024 filter: 1024 box: 1024
  max workgroup size zero: 1024 costs: 1024 b1: 1024 bn: 1024 wta: 1024 transpose: 1024
initializing...
selected 0 cameras from 214 in 0.024 sec
Loading photos...
Reconstructing depth...
finished depth reconstruction in 0.015 seconds
Device 1 performance: 0 million samples/sec (CPU)
Device 2 performance: 0 million samples/sec (GeForce GTX 580)
Generating mesh...
Finished processing in 0.54 sec (exit code 0)


 

[mr_cg]

I have exactly the same problem "Can't build model" with v0.9.1 b1684.

The alignment of the cameras seem to be pretty good. But to build the geometry is not possible.
In the logfile i can see that "0 cameras" are selected and i think this is the problem here.
What is the criteria for the selection of the cameras from the software???

Could it be the case that i do not have enough points?
I have only 948 point (24 pictures) because the object is completely white.

Logfile:
selected 0 cameras from 24 in 0 sec
Loading photos...
Reconstructing depth...
finished depth reconstruction in 0 seconds
Device 1 performance: 0 million samples/sec (CPU)
Generating mesh...
0 points extracted
Finished processing in 0 sec (exit code 0)
Loading project...
loaded project in 0.031 sec
Finished processing in 0.031 sec (exit code 1)


Any idea how to build the geometry?
Any setting i need to change in the options?

[Alexey Pasumansky]

Hello mr_cg,

Probably you have "reuse depth maps" option checked on in the Build Geometry dialog, while there are no depth maps in the chunk. Could you please try to run Build Geometry again with the unchecked re-use option?

[mr_cg]

Unfortunately it was already unchecked.
See used settings in attached screenshot.

[Alexey Pasumansky]

Hello mr_cg,

Then the problem is connected with low number of matches for each pair of overlapping images (could be checked in View Matches dialog from Tools menu).

If the alignment was now performed already with High accuracy setting, I recommend to realign the set with higher accuracy to get more valid matches for each pair.

[mr_cg]

How much points (total, valid, unvalid ) are required and how to check how much are missing?

Thanks

[Alexey Pasumansky]

Hello mr_cg,

The threshold values may vary a little bit, but having about hundred or two valid matches between a pair of photos will guarantee the depth map reconstruction between these images.

[jondandois]

I was having this problem today too. I checked the console output at Alexey's recommendation earlier in the thread and found that the build geometry step was trying to load the photos from a different folder level.  I moved the photos to where Photoscan wanted them and things run smoothly from there.  I think the problem was on my end and I had moved the PSZ file for some reason I can't currently recall.