Poor Dense Cloud Generation - Metashape Pro 1.5.1

[GH3D]

Hi,

I've recently upgraded to version 1.5 from 1.4.5 and seem to be having a problem with the quality of the dense cloud generated in the later version. The project consists of 2138 images taken from aerial and terrestrial viewpoints which i have successfully aligned and georeferenced  and split in to smaller chunks for processing. Having processed a number of chunks using version 1.4.5 the dense cloud produced is of a good quality (set to high density, aggressive filtering) but is taking a while to produce, where as the process seems quicker in 1.5 (inc 1.5.1) but the dense cloud contains a lot of artefacts and is basically unusable. I've attached a couple of images to highlight the problem.

Has anybody else had similar issues and been able to resolve them?

current PC setup is as follows:
Intel Core i9 -9900X (10 cores @ 3.5GHz)
128GB RAM
2 x Nvidia RTX 2080Ti


 

[RHenriques]

In my case the dense point clouds are very good. They were worst in the first betas of 1.5 when compared to 1.4.x mainly due to filtering. In the latest 1.5 versions, including this one, they are awesome.
It seems, in your case, that something is "contaminating" the model. Probably moving plants and background. It's painful but probably you need to mask a lot.

[Alexey Pasumansky]

Hello GH3D,

Have you tried to generate the dense cloud for the same project/chunk that has been processed in the version 1.4 using the same settings in order to compare the outputs?

Looking on the the provided problematic image I would assume that the problem could be related to the alignment or some issues with the calibration parameters estimation. Or even for some reason instead of the original cameras some other cameras were accidentally used (for example, due to change path operation).

[GH3D]

Hi Alexey,

I've tried processing various chunks in various versions with the same outcome. I reprocess the same chunk as shown in the 1.4 image in version 1.5.1 and post up an image of the results for comparison in the morning. I have also attached an image of a merged dense cloud (medium, aggressive) of the same area done in a previous version  (and different computer) but with fewer images (no terrestrial images). Really struggling to understand why this is happening but hopefully we can get to the bottom of it.

Many thanks

[Mak11]

Hi Alexey,

I've tried processing various chunks in various versions with the same outcome. I reprocess the same chunk as shown in the 1.4 image in version 1.5.1 and post up an image of the results for comparison in the morning. I have also attached an image of a merged dense cloud (medium, aggressive) of the same area done in a previous version  (and different computer) but with fewer images (no terrestrial images). Really struggling to understand why this is happening but hopefully we can get to the bottom of it.

Many thanks

If the chunk your are processing in 1.5.x includes terrestrial images (which weren't in the projects processed in 1.4.x) then this may very be the cause of the issue. Those images are either nor aligning correctly or contain features which are messing up the depth maps/Dense Cloud. The only way to compare both versions would be to run the exact same project in 1.4 & 1.5.

Mak

[GH3D]

Hi Mak

The two images in the first post are from the same dataset, which included both the aerial and terrestrial images. I am currently reprocessing the chunk shown in the clean image (previously processed using 1.4.x) in version 1.5.1 and will post the result once complete. Hopefully this will highlight the problem.

Many thanks

[GH3D]

I've now reprocessed the same chunk shown in the 1.4 example with the latest version. These results are using the exact same datasets with the exact same alignment processed with the same settings, the only difference being the version that they have been processed with. i have reattached the original image for comparison.

Any ideas?

[Alexey Pasumansky]

Hello GH3D,

Can you re-save the project in PSZ format with only alignment results and image thumbnails and send it to support@agisoft.com? We'll try to understand what might be causing the issue without having all the images.

[GH3D]

No problem, i will try and send it over soon.

Many thanks for your assistance with this.

[Mak11]

Do the photos contain noise (caused buy high ISO for example)? I noticed that 1.5 is a lot more sensible to bad photos than 1.4&1.3.

Cheers

Mak

[plabedz]

Hello,

I've got exactly the same problem as mentioned. In the same conditions and settings of generation of a dense point cloud, version 1.4.5 gave good results while 1.5 produced extremely noisy reconstruction. The Very High Quality setting in 1.5 is like a Low Quality setting in 1.4 and the High Quality in 1.5 is only denser than Low, but with the same amount of noise.
I'm looking forward to seeing the solution.

Peter

[Alexey Pasumansky]

Hello GH3D,

Thank you for sending the project, still checking the issue. Just for case, are you using the "max_neighbors" tweak in the version 1.5?


Hello Peter,

Can you provide some sample screenshots demonstrating the difference in the dense cloud quality between the two versions and the project with the alignment results and thumbnails to support@agisoft.com?

[GH3D]

Hi Alexey,

Thanks for looking in to this and I'm pleased you received the data ok. I can confirm that we are using the max neighbour tweak with a setting of 65.

Mak, sorry for the slow reply, having looked through the images, they generally appear to be free of noise and were mainly shot at a low ISO value. It's good to know for future reference though that 1.5  works better with cleaner images.

Many thanks

[plabedz]

Hello Alexey,

Here are some screenshots presenting the difference between 1.4 and 1.5 in both high and low quality settings. I will prepare the project and send it to support. Thank you for your help.

Peter

[dronesurveyconsultancy]

Is there already a solution to this problem?
Having the same issues...