Region OF Interest

How can you define the region of interest after adding GCPs and calibrating prior to processing point cloud, DSM etc? At this stage there only appears to be the camera positions in the 2D screen to set the region of interest from. Seems pointless to run all processing options to get the DSM available in the 2D screen so you can then add the region of interest then have to re-run processing options again??

Hi @PPGroup ,

It is possible to draw a Region of interest at any stage of the processing. In fact, it is recommended to add it before the Calibrate or the Densify step in order to have an immediate effect like you said. Adding a Region of interest after the Densify step requires reprocessing to have an impact on the results.

For more information: How to use the Region of Interest in PIX4Dmatic

Best regards,
Rosana (she/her)

@PPGroup for now the usual workflow I use is to look at the area defined by my initial camera positions, combined with the Map or Satellite background map view. This usually gives me a good idea of where to limit the region of the project. That said, I agree that we need to extend the capabilities, for example we need to make the region of interest visible in the 3D view, so that it’s easier to create and adjust right after the calibration was done (and before the dense, dsm,…). We have this on our roadmap.

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Hi there,
Unfortunately this isn’t possible for anywhere in Australia with the 2D basemap satellite view. There is nothing recognisable anywhere in the country. Is there a way to use our own WMS provider, or possibly Pix4D switching to another provider that has coverage (there are many that can provide a better view). Even Google is 20x better unfortunately :frowning:

See the links below for example. Pretty safe to zoom in anywhere in Australia and you will get a similar result.


Thanks for reporting the issue, sorry that’s happening, I’m going to inform Maptiler (the map provider) about this. If they don’t fix it, we’ll look into adding options.

Awesome, thankyou.
A basic map with the option of connecting to a WMS would be fantastic as well, as most Australian government states provide high resolution free WMS services that are impressive in quality, usually equal to paid services or at times even better

I typically won’t be able to define my region of interest before I’ve processed the dataset all the way to the orthomosaic because I want to use it to have smooth edges on my orthomosaic, but still cover as much ground as possible with the dataset at hand.

So there is no other option than running the whole processing again after that? Wouldn’t it be better if the export could cut the orthomosaic along the region of interest boarders? At least I don’t seem to find an option for that. And the article about the topic doesn’t indicate clearly how early in the process the region of interest needs to be defined to affect the process.

right now the region of interest is indeed kind of limited, as it’s only possible to draw it in the 2D view and it only affects results after the calibration (if you process them with the ROI created beforehand)

a first improvement we plan to make is to make the definition of the ROI available in the 3D view, that should help to define it more precisely, as well as to have top and bottom boundaries (can be useful to remove cables, trees,…)

further down the road, we’d like to be able to apply a ROI only to an export, this will require some rework and further processing, as the orthomosaic would need to be re-tiled so that it fits the export, but that should be feasible too.

we’d like to make it easy to import a file for the ROI, that way if you have pre-defined areas to limit the project to, it’s easier to import and apply rather than to draw them from scratch.

and the best will be once we can create multiple of them :slight_smile:

good point, thanks for sharing the feedback!

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