Mesh is clipped/missing near ROI boundary while all other outputs respect the ROI correctly

[maal]

Environment

PIX4Dmatic version: 2.8.0
Project: 260803_Gartenfeld
Camera: DJI Mavic 3M, 1277 images, 6.4 ha, GSD 1.0 cm
CRS: ETRS89/UTM33N + DHHN2016 (EPSG:25833 + 7837)
GCPs: 19 GCPs, 6 checkpoints

Description

I processed a project using a Region of Interest (ROI). The ROI was defined once and used for all outputs.

All outputs except the mesh honour the ROI exactly and correctly:

Image 1: 2D outputs: orthomosaic and DSM are generated up to the ROI boundary without any gaps. I marked the ROI and the corner of the building, what is missing in 3d mesh.

Image 2: 3D point cloud: densified points extend cleanly up to the ROI boundary.

Image 3: 3D Gaussian Splatting: also complete up to the ROI boundary.

Images 4 and 5: Only the textured mesh is incomplete. At one building corner that lies clearly inside the ROI, parts of the mesh are missing. The missing area is not a thin edge artifact along the boundary; it is a wedge-shaped area set back from the ROI boundary by several metres, so the mesh edge does not follow the ROI polygon at all in this region.

Expected behaviour

The mesh should cover the full extent of the ROI, consistent with the point cloud, the 3DGS, the orthomosaic and the DSM.

Actual behaviour

The mesh is cut back well inside the ROI at this building corner, leaving a gap in the geometry and texture. Image coverage and point density in that area are good, as visible in the point cloud, so the input data does not appear to be the cause.

Questions

Is the ROI applied differently during mesh generation than during point cloud, orthomosaic and DSM generation, for example with an additional internal buffer or a different clipping logic?
Is there a known limitation where mesh triangles near tall vertical structures close to the ROI boundary get discarded?
Is there a workaround other than enlarging the ROI, for example a specific processing setting?

I can provide the project file, the ROI geometry or a log file on request. We’re heavily using Pix4dMatic almost daily, this error never occured before. Please provide some help!

Thanks a lot!

Best, Manuel

[Alvaro_Santiago]

Hi @maal

We will take a look at this issue with the mesh and the ROI. If we need more information, I will contact you.

Regards

[Alvaro_Santiago]

Hi @maal

Could you please upload this project to this folder in OPF format?

Thank you in advance

[maal]

what exactley do you need? images i cannot share due to nda

[maal]

Hi Alvaro, thanks for your help.

@Alvaro_Santiago could you be so kind and answer, so you can go on solving this issue? Shall I upload everything (expect the images)? Do you need all the results and the calibration, too?

[drones6]

@Pierangelo_Rothenbuhler @Alvaro_Santiago please help us! this is 22 days open now, without us getting a reply… that’s a little bit frustrating to be honest. I provided so detailed description com’on, please!

please answer my last question, so i can upload @Alvaro_Santiago

[Alvaro_Santiago]

Hi Manuel,

Agreed; the description is so detailed, but the developer needs the entire project to investigate. I shared with you a folder to upload all the information so we can download and try to replicate the error.

The OPF project should be exported with all the options selected.

Regards

[drones6]

Hi Alvaro,

agreed, too. Your answer on that was missing, I will upload it now, with all images.

We flew this project again (it’s a monthly job), and again exactly at this position the mesh is not complete. It’s looks like it’s an repeating error/bug, from my point of view:

Please do me a favor and keep me updated, best would be weekly, if you can manage. My client is permanently asking… Thanks!

[drones6]

@Alvaro_Santiago I sent you two requests for access to the Google Drive folder, please let me know once this is granted…