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View OSM changes in time
Geofrabrik data
First let's get historical OSM data these can be downloaded from Geofabrik latest and full history select the country and download internal.osh.pbf - OSM login is required to download.
Then grab latest.osm.pbf which is up-to-date file with no history.
Osmium
Download Osmium
Prepare data for certain date as baseline e.g. Jan 1st 2019
cut the area from whole country to bounding box of interest
and optionally convert it to osm xml file (needed for JOSM; not needed for Maperitive)
Prepare latest data by cutting the same area
remove everything apart from paths and tracks
and optionally convert to osm xml
Compare
There are varios scripts and tools which can be used like basic perl script Osmdiff or big GIS package QGIS (which I never had luck with to understand it)
I decided to go first with JOSM which's my tool-to-go for map edits. It can open osm xml, but was quite sluggish with the files (filtering historical extract for only some entities would help).
Next I tried Maperitive (sorry, Win only) which I found better option in this case. Simply turning on/off layer with added path/tracks in current data file did the trick (had to edit a bit rules of Maperitive renderer, but that's different story).
2019 -
July 2020 -
Timelapse
To create timelapse more historical snapshots are needed. To avoid processing big file many times I though sorting it would help (note this is pretty RAM intensive operation, for Czech republic - relatively small country - it didn't work on less than 16GB RAM and ate 8GB swap as well).
however it didn't
so I wrote perl script to create ways from historical country dump
this produced point-at-time files with paths and tracks only
In Maperitive make png for each of them (we already have latest and Jan 2019 from earlier on) by simply turning on/off layers and export (CTRL+E).
To make a movie I used imagemagick's utility convert
which produced video below, each frame is one second.
https://tube.tchncs.de/videos/watch/b32b0f29-aadc-48d3-8e65-ee4d5b2a8226