buildings import

[mikelmaron]

@iandees used https://github.com/Microsoft/USBuildingFootprints to build a layer of missing buildings in Detroit

Could be extended to whole region

There are also open data on buildings which would be good to also assess

What would import process look like? Presumably want some kind of tasking for human review. Maybe LA Buildings Import is a model

cc @jharpster

[hampelm]

I would love to learn how an automatic import would work. I've seen them from afar but don't know the current best practice to implement. And if there's manual labor to be done I'm in.

For the SEMCOG buildings ata, the past concern has been the license... maybe we could get them to open it up more for OSM?

The "custom license" on that page reads:

The following data is provided by SEMCOG for informational use only. Every reasonable effort has been made to assure the accuracy of this data however portions of the information may be incorrect. When using this data please Source: SEMCOG.

[iandees]

I spent some time on the SEMCOG buildings dataset this morning.

I started with converting the Shapefile download from the SEMCOG portal through ogr2ogr to get GeoJSON. That GeoJSON is zipped and available here.

I passing it through tippecanoe to get an mbtiles for use with OSM QA Tiles and tilereduce. The command I used is:

cat ~/Downloads/detroit-buildings.geojson | tippecanoe \
    --buffer=0 --no-duplication --no-clipping \
    --base-zoom=12 \
    --maximum-zoom=12 \
    --minimum-zoom=12 --no-feature-limit --no-tile-size-limit --no-line-simplification \
    -o ~/Downloads/detroit-buildings.mbtiles

But the resulting mbtiles file has all the buildings slightly shifted to the northwest and simplified (where the raw GeoJSON matches the shapefile).

Once this is solved, I do have a tile-reduce script written that will output GeoJSON for the buildings that are missing from OSM and add addresses and improve metadata (add start_date and height) where there are existing OSM buildings that don't have these tags.

[nickballen]

Confirming SEMCOG is the best local footprint source. The footrprints are attribute-rich and include parcel-based addresses.

Since it is based on 2013 imagery, I recommend it be joined with the Detroit demolition list to cover changes since it was produced:

https://data.detroitmi.gov/Property-Parcels/Detroit-Demolitions/rv44-e9di

I've reached out to SEMCOG in November about licensing as ODbL or Creative Commons. They have indicated interest in the import and have previously provided this data restriction-free to Esri.