Change in hardware leads to sparser depth maps

[Alexandros21]

Hi all,

I've started using a Cloud service for my work and I also installed Metashape there. I ran a dataset both on the cloud and my local machine, using the exact same Metashape version (1.7.1. build 11797) and the exact same tweaks (BuildDenseCloud/max_neighbors = -1).

However, the generated depth maps in the Cloud are sparser than the depth maps built in the local machine and consequently, they lead to a much sparser pointcloud. Could you please help me understand what might be the issue? Could it be eg. because of the different GPU? Here is the hardware that I've used:

Local machine:
Processor Intel Core i7-7700k CPU @ 4.2 GHz
RAM 64 GB
GeForce GTX 1080 (20 compute units @ 1733 MHz, 8192 MB)

Cloud:
AMD EPYC 7V12 64-core @ 2.44 GHz
RAM 112 GB
Radeon Instinct MI25 MxGPU (gfx900) (64 compute units @ 1000MHz, 16064 MB)

Thank you in advance,
Alexandros

[Mak11]

I've been suspecting for a little while that their are issues/differences with the OpenCL path compared to the CUDA path.
Hopefully the Agisoft team can finally take a closer look into this..

Mak

[Alexey Pasumansky]

Hello Alexandros,

Can you share any small sample project to support@agisoft.com which contains the two chunks with the depth maps generated based on the same alignment results on local and cloud configurations, where the difference between the depth maps can be observed?

[Alexandros21]

Hi Alexey,

Thank you for your answer. I sent the sample project at the provided address.

Best regards,
Alexandros

[Alexey Pasumansky]

Hello Alexandros,

Thank you for sharing the data, we will check it and see, if the problem could be reproduced on similar hardware. At a brief glance I see that the depth maps are

Can you please confirm, if you have only Radeon card selected in GPU Preferences tab on cloud machine, or whether "use CPU" option has been enabled as well?
If you have also the processing log saved for the cloud based operation, it could be also helpful to us.

[Alexandros21]

Hi Alexey,

No, I had "use CPU" option disabled. I don't have the log of the run that I sent you, so I built again depth maps on the Cloud and I saved it. Please find the log attached in this post.

Best,
Alexandros

[Alexey Pasumansky]

It appears that the issue has been related to the outdated AMD driver installed for cloud GPU instances. In Metashape 1.8.1 the problem has been workarounded on our side (as it is not clear, if the driver update for cloud GPUs are expected any time soon) and the results obtained using Radeon Instinct (and other cloud AMD GPUs) should be similar to local processing results or results obtained with the use of cloud NVIDIA GPUs.