Road subsidence and potholes: 4 datasets available, 80, 116, 172 and 265 images

[Gordon]

For anyone that wants some images to play with, I have uploaded some Mavic 2 Pro images, 5472 X 3648 pixels. My 4GB VRAM GPU wont extract features at full size, but will if you reduce by 1.5X to 3644 pixels.
All 4 sets are of various sections of a nearby gravel road in poor condition with plenty of potholes and corrugations in places.

GSDs are mostly <1cm, images taken from 25-30metres AGL, mostly off-nadir, along the road and from the sides. Flight was manual with the drone stopped for each image, so no rolling shutter distortion.

DTM

Small part of a point cloud

The 265 image dataset took 19 hours with these settings-
||auto-boundary: true, dem-resolution: 1, dsm: true, dtm: true, feature-quality: ultra, gps-accuracy: 8, matcher-neighbors: 12, mesh-size: 250000, orthophoto-resolution: 0.6, pc-filter: 5, pc-quality: high, pc-rectify: true, resize-to: -1, use-3dmesh: true|
|Average GSD:|0.6 cm| Area:|48,631.13 m²|

116 image dataset took 4h 52m
||auto-boundary: true, dem-resolution: 2, dsm: true, dtm: true, feature-quality: ultra, gps-accuracy: 8, matcher-neighbors: 10, mesh-size: 250000, orthophoto-resolution: 0.6, pc-filter: 5, pc-quality: ultra, pc-rectify: true, resize-to: -1, use-3dmesh: true|
|Average GSD:|0.51 cm| |Area:|1,500.34 m²|

Processed with i7 10700K 3.8GHz CPU, 96GB 2.933GHz RAM
NVIDIA GeForce GTX 1650 Super 4GB Graphics card

https://drive.google.com/drive/folders/1ast12U4qPT2473nVQuLRjntCzDpmicXc?usp=sharing

[Gordon]

From the 80 image set-

Section of road showing effect of water running down the road 4 months ago, not yet repaired.

Subsidence and potholes with a high ridge in the middle of the road, where regular cars scrape their undersides (diagonal lines perhaps due to not being able to image from the left side, due to trees)

3D model of the subsidence area, showing where 4WDs have attempted to avoid it on the right side, through boggy ground

[smathermather]

@Gordon

Subsidence and potholes with a high ridge in the middle of the road, where regular cars scrape their undersides (diagonal lines perhaps due to not being able to image from the left side, due to trees)

You’ve hit the (prior) decimeter precision limit in ODM with this. If you updated and re-ran, you wouldn’t see that contouring effect anymore (or you would see it at the centimeter level instead, anyway).

Although it is kind of fun that I can count how many decimeters deep those holes are using the dem alone.

BTW: these are fantastic.

[Gordon]

@smathermather

If you updated and re-ran, you wouldn’t see that contouring effect anymore (or you would see it at the centimeter level instead, anyway).

Thanks
I’m on the latest version now, I think those contours are centimetre level!

[smathermather]

Ha! Wow.