2,704 karma · joined December 27, 2011
Author and Technical Analyst of https://tech.marksblogg.com/
I had to look into ~19 imagery firms for some telco work in Canada last year.
There are private jets that can capture 10cm imagery and can pick the ideal weather window to fly in.
There are also firms that fly balloons 20 - 80 KM off the ground that can capture 4cm imagery.
The space is pretty busy.
There should be enough SQL in the blog to re-purpose extracting out the Wildberries locations and seeing where they land on top of. I've never heard of this firm before you mentioned it.
From Google:
> Citibank operates over 2,300 ATMs within more than 600 U.S. branches, with a total network of over 65,000 fee-free ATMs
So the 57,163 Citibank locations are probably a combination of their branches and ATMs.
Update: I reviewed Alltheplaces a while back, they scrape company websites for store locations. They reported 68,227 locations for Wildberries. ATP is one of the sources Overture use but they seem to use 1.55M of the records from their 19M-record dataset. https://tech.marksblogg.com/alltheplaces.html
The Airport in Tartu, Estonia had a navigation upgrade last year in order to help mitigate navigation jamming that's taking place in the region. https://www.eans.ee/en/uudised/tanasest-saab-tartu-lennuvalj...
Defcon had a great talk on all the different navigational systems pilots can use and a note at the end that these shouldn't be decommissioned at the rate they're experiencing atm https://www.youtube.com/watch?v=wSVdfOn737o
India has ~4x the population of the US so the ratio of buildings isn't much of a surprise.
I have some analysis around that topic in the middle of this post: https://tech.marksblogg.com/overture-land-cover.html
DuckDB querying the data should be able to return results in milliseconds if the smaller columns are being used a better if the row-group stats can be used to answer queries.
You can host those Parquet files on a local disk or S3. A local disk might be cheaper if this is exposed to the outside world as well as giving you a price ceiling on hosting.
If you have a Parquet file with billions of records and row-groups measuring into the thousands then hosting on something like Cloudflare where there is a per-request charge could get a bit expensive if this is a popular dataset. At a minimum, DuckDB will look at the stats for each row-group for any column involved with a query. It might be cheaper just to pay for 400 GB of storage with your hosting provider.
There is a project to convert OSM to Parquet every week and we had to look into some of those issues https://github.com/osmus/layercake/issues/22
The Parquet pattern I'm promoting makes working across a wide variety of datasets much easier. Not every dataset is huge but being in Parquet makes it much easier to analyse across a wide variety of tooling.
In the web world, you might only have a handful of datasets that your systems produce so you can pick the format and schemes ahead of time. In the GIS world, you are forever sourcing new datasets from strangers. There are 80+ vector GIS formats supported in GDAL. Getting more people to publish to Parquet first removes a lot of ETL tasks for everyone else down the line.
I've only seen Maxar publish one night time image and that was of Dubai. I suspect smaller buildings in not so well lit areas could end up getting missed out.
SAR imagery would work well for seeing at night and through clouds but I'm not sure what the state of AI building footprint detection is with SAR atm.
TomTom did a few write ups on their contribution, this one is from 2023: https://www.tomtom.com/newsroom/behind-the-map/how-tomtom-ma...
If you have QGIS running, I did a walkthrough using the GeoParquet Downloader Plugin with the 2.75B Building dataset TUM released a few weeks ago. It can take any bounding box you have your workspace centred on and download the latest transport layers for Overture. No need for a custom URL as its one of the default data sources the plugin ships with. https://tech.marksblogg.com/building-footprints-gba.html
If you're using ArcGIS Pro, use this plugin: https://tech.marksblogg.com/overture-maps-esri-arcgis-pro.ht...
Shapefiles shouldn't be what you're after, Parquet can almost always do a better job unless you need to either edit something or use really advanced geometry not yet supported in Parquet.
Also, this is your best source for bulk OSM data: https://tech.marksblogg.com/overture-dec-2024-update.html
If you're using ArcGIS Pro, use this plugin: https://tech.marksblogg.com/overture-maps-esri-arcgis-pro.ht...
The real win will be satellite-to-satellite transmissions where any data collected by the constellation is passed to the satellite that'll next fly over a ground station. This will lower the time from capture to analysis considerably. The fresher the data, the more valuable it is.