Here are the visuals re: trees - https://i.imgur.com/R0W4q4O.png
What did you do to actually count trees? Even from aerial Lidar it can be a bit finicky for closed canopies.
Here is the first pass, https://i.imgur.com/f7Gpxmm.png, it under counted and also even counted my house as a tree, lol.
The blog post and paper [1] describe a promising approach to solving related problems at previously impossible scale and quality: I am currently exploring methods to better represent seasonal land cover changes that would improve wind power generation forecasting and this paper provides a great starting point.
I hope DINOv3 can inspire more work like this - and I would encourage any curious mind to play with that model! I was amazed by its capability to distinguish between fine object details. For example, in a photo of a bicycle, the patch embeddings cleanly separated the background from the individual spokes of the wheel.
It's a nice piece of work. I especially like the sections on data cleaning and registration, as that seemed to have been one of the limiting factors of the previous approaches.
I am sceptical about how accurately you can predict heights for specific trees from mono-images, but I think for cases where you just need to be right on average (e.g. biomass estimation, fuel load estimates) it's a great approach.
Maybe there are some ulterior motives, but they do also just do a little bit of "feel-good" research.
This was also in collaboration with the World Resources Institute and the University of Maryland, so it's not a 100% facebook project.
> CHMv2 is derived from single-date imagery, where the acquisition process selects the best available image within a target period (2017 -2020). This limits the direct use of the released CHMv2 data for attributing canopy height to a specified year of interest. To support change applications, we provide the image acquisition date associated with each prediction in the dataset metadata.
So generally a few years out of date, but the dataset is transparent about when each image was taken.
The tree outside of house is not 9 feet tall per. I have a 2 story house and it easily towers 10 feet higher than my house.
Additionally, there are several Royal Palms that are close to 50ft and they show as being only 15 feet.
> We additionally release a global GeoTIFF of input image acquisition date, where pixel values encode year minus 2000 (e.g., 18.25 indicates April 2018)
That being said, I am sceptical on how accurate mono-depth models can be on a single tree basis. I would probably trust them to do large scale biomass estimates, but probably not single tree height assessments.
