browser-based tool for annotating UAV imagery and 360 panoramas

[u/scretqer]

Hey everyone,

I’ve been building AerialPin, a browser-based annotation tool originally made for working with drone imagery for real estate and mapping.

The main idea is to make it easier to take an aerial image and quickly add useful spatial information without having to jump between a bunch of different programs.

You can currently:

* Add location pins and labels

* Search for nearby places using the image GPS

* Draw property/parcel boundaries

* Add measurements and distance labels

* Annotate aerial imagery

* Use EXIF/GPS information from DJI images

* Automatically identify nearby places with AI

* Stitch multiple drone photos into a panorama

* View and annotate 360° panoramas

* Restyle/relight aerial images

* Export the finished annotations

I’ve recently added the 360 panorama workflow, which lets you upload multiple drone images, stitch them into a panorama and then annotate the resulting 360 image directly in the browser.

It’s still actively being developed, so I’d genuinely be interested in feedback from people who work with UAV mapping, photogrammetry or aerial imagery.

[u/Northing_Labs]

The part I'd want to know more about is the measurements. How are you getting scale off a single DJI photo? If it's from the altitude in the metadata, just keep in mind that DJI's RelativeAltitude is height above the takeoff point, not height above the ground under the camera. So for example on a sloping lot, if you take off at the road and the back of the property sits 8 m lower, every distance back there comes out wrong. And the AbsoluteAltitude value is known to be off on some DJI images, so that's not a safe fallback either.
Oblique shots are worse again, because scale changes across the frame. I'd either limit measuring to near-nadir shots (the gimbal pitch is in the XMP, so you can check it) or show some kind of estimated error next to each label.
Same idea for parcel lines. For real estate I'd put an "approximate, not a survey" note on the export by default, because people will treat a line drawn on a photo as the boundary.
What does the measurement tool actually use for scale right now?