A pipeline to simplify building a set of training data for aerial-imagery- and OpenStreetMap- based machine learning. The idea is to use OSM QA Tiles to generate "ground truth" images where each color represents some category derived from OSM features. Being map tiles, it's then pretty easy to match these up with the desired input imagery.

• OSM QA tile data copyright OpenStreetMap contributors and licensed under ODbL
• Mapbox Satellite data can be traced for noncommercial purposes.

The easiest way to use this is via the developmentseed/skynet-data docker image:

First, create a docker.env file with the contents including your MapboxAccessToken:

MapboxAccessToken=YOUR_TOKEN 

Then run:

docker run -v /path/to/output/dir:/workdir/data --env-file docker.env developmentseed/skynet-data download-osm-tiles docker run -v /path/to/output/dir:/workdir/data --env-file docker.env developmentseed/skynet-data

The first line downloads the OSM QA tiles to /path/to/output/dir/osm/planet.mbtiles. If you've already got that file on your machine, you can skip this.

The second builds a training set using the default options (Roads features from OSM QA tiles, images from Mapbox Satellite). To change the data sources, training set size and other options, add the relevant environment variables to the docker.env file , one per line.

You can also create the docker images yourself using docker-compose. Similarly to the quick-start above, make sure your docker.env file has your MapboxAccessToken and any other environment variables you want to set. Then run:

docker-compose build 

to build your local docker image, and

docker-compose run data download-osm-tiles docker-compose run data 

to download the OSM QA tiles, and run the data collection as specified in docker.env. By default the collected data will be saved into the data directory, but you can overide it by using -v /path/to/output/dir:/workdir/data after docker-compose run data similar to the pre-built instructions above.

The make commands below work off the following variables (with defaults as listed):

# location of image files IMAGE_TILES ?= "tilejson+https://a.tiles.mapbox.com/v4/mapbox.satellite.json?access_token=$(MapboxAccessToken)" # which osm-qa tiles extract to download; e.g. united_states_of_america QA_TILES=planet # location of data tiles to use for rendering labels; defaults to osm-qa tiles extract specified by QA_TILES DATA_TILES ?= mbtiles://./data/osm/$(QA_TILES).mbtiles # filter to this bbox BBOX ?= '-180,-85,180,85' # number of images (tiles) to sample TRAIN_SIZE=1000 # define label classes output CLASSES=classes/roads-buildings.json # Filter out tiles whose ratio of labeled to unlabeled pixels is less than or # equal to the given ratio. Useful for excluding images that are all background, for example. LABEL_RATIO ?= 0 # set this to a zoom higher than the data tiles' max zoom to get overzoomed label images ZOOM_LEVEL ?= 17 

You can override any of these parameters in your docker.env and make a full training set using the instructions above.

• Install NodeJS v4.6.2
• Install tippecanoe
• Install GNU Parallel
• Install shuf
• Clone this repo and run npm install. (Note that this includes a node-mapnik install, which sometimes has trouble building in bleeding-edge versions of node.)

make data/sample.txt

This just does a simple random sample of the available tiles in the given mbtiles set, using tippecanoe-enumerate. For more intelligent filtering, consider using tippecanoe-decode to examine (geojson) contents of each tile.

Build label images: make data/labels/color or make data/labels/grayscale. Uses the CLASSES json file to set up the rendering of OSM data to images that represent per-pixel category labels. See classes/water-roads-buildings.json for an example. Rendering is with mapnik; see the docs for more on filter syntax.

Download aerial images from a tiled source: make data/images

Heads up: the default, Mapbox Satellite, will need you to set the MapboxAccessToken variable, and will cost you map views!

Preview the generated data by opening up preview.html?accessToken=<mapbox access token>&prefix=/path/to/data in a local web server.