Readme for filtering tool, and fixed the license

filter/README.md

@@ -0,0 +1,35 @@
+# Filtering OSM by external dataset
+
+When you got points of multiple categories, an Overpass API request may fail
+from the number of query clauses. For that, you would need to filter the planet
+file yourself. First, prepare a list of categories and dataset points:
+
+    conflate.py profile.py -f points.lst
+
+Then compile the filtering tool:
+
+    mkdir build
+    cmake ..
+    make
+
+Download a planet file or an extract for the country of import, update it to the minute,
+and feed it to the filtering tool:
+
+    ./filter_planet_by_cats points.lst planet-latest.osm.pbf > filtered.osm
+
+This will take an hour or two. The resulting OSM file should be used as an input to
+the conflation tool:
+
+    conflate.py profile.py --osm filtered.osm -c changes.json
+
+## Authors and License
+
+The `filter_planet_by_cats` script was written by Ilya Zverev for MAPS.ME and
+published under Apache License 2.0.
+
+The `xml_centers_output.hpp` and `*.cmake` files are based on
+[libosmium](https://github.com/osmcode/libosmium) code and hence published
+under the Boost License terms.
+
+`RTree.h` is under public domain, downloaded from
+[this repository](https://github.com/nushoin/RTree).

filter/xml_centers_output.hpp

@@ -1,8 +1,10 @@
 /*
 
-This file is part of Osmium (http://osmcode.org/libosmium).
+This file is based on xml_output_format.hpp from the Osmium library
+(http://osmcode.org/libosmium).
 
 Copyright 2013-2017 Jochen Topf <jochen@topf.org> and others (see README).
+Copyright 2017 Ilya Zverev <ilya@zverev.info>, MAPS.ME
 
 Boost Software License - Version 1.0 - August 17th, 2003