Based on osmlab/osm-animate.
Uses datamaps, pngquant, gifsicle, and netpbm. If on a Mac,
brew install pngquant gifsicle netpbm libpng
If on Linux,
sudo apt-get install gifsicle pngquant libpng-dev libexpat1-dev
And in either case:
git clone https://github.com/ericfischer/datamaps.git
cd datamaps
make
Then come back here and make "snap":
cd ..
make snap
You need an OSM extract with timestamps, like the ones that Mapzen hosts. For instance, let's try Brasilia. Copy the URL for the OSM XML download for the city you want, and download it:
curl -O https://s3.amazonaws.com/metro-extracts.mapzen.com/brasilia_brazil.osm.bz2
Then extract the vectors from the OSM data into a datamaps flat file:
bzcat brasilia_brazil.osm.bz2 | ./snap > brasilia.snap
and then encode them with datamaps:
cat brasilia.snap | ./datamaps/encode -z20 -m32 -o brasilia.dm
Then, to make the gif, do:
./perform brasilia
which reads brasilia.snap to find the bounds of the area and the range of times represented,
and makes multiple renderings of brasilia.dm into a temporary directory of images, brasilia.out,
and ultimately combines them into brasilia.gif.