osm2ch

Convert *.osm.pbf files to CSV for contraction hierarchies library

• osm2ch
  • About
  • Installation
  • Usage
  • Example
  • Output format
  • Dependencies
  • License

About

With this CLI tool you can convert *.osm.pbf (Compressed Open Street Map) file to CSV (Comma-Separated Values) file, which is used in our contraction hierarchies library.

Under the hood it uses osm2gmns library (Go port of osm2gmns) to build a macroscopic graph with turning movements, then this CLI performs edge expansion and contraction hierarchies.

What it does:

• Builds macroscopic network from OSM via osm2gmns;
• Generates turning movements at intersections;
• Performs edge expansion (each macro link becomes a vertex, movements become edges);
• Filters U-turns;
• Supported types of restrictions (internally processed in osm2gmns): - only_left_turn; - only_right_turn; - only_straight_on; - no_left_turn; - no_right_turn; - no_straight_on.
• Prepares contraction hierarchies;
• Outputs CSV files with geometry in WKT or GeoJSON format.

Agent type filtering is handled by osm2gmns (e.g. auto, bike, walk).

PRs are welcome!

Installation

• Via 'go install':

  go install github.com/LdDl/osm2ch/cmd/osm2ch@latest

  After installation step is complete you can call 'osm2ch' from any place in your system.

• Or download prebuilt binary from Releases and add it to your PATH.

• Docker:

  docker pull dimahkiin/osm2ch:latest

Usage

osm2ch -h

Output:

Usage of osm2ch:
  -file string
        Filename of *.osm.pbf file (it has to be compressed) (default "my_graph.osm.pbf")
  -out string
        Filename of 'Comma-Separated Values' (CSV) formatted file (default "my_graph.csv")
        E.g.: if file name is 'map.csv' then 3 files will be produced: 'map.csv' (edges), 'map_vertices.csv', 'map_shortcuts.csv'
  -geomf string
        Format of output geometry. Expected values: wkt / geojson (default "wkt")
  -agents string
        Comma-separated list of agent types. Expected values: auto,bike,walk (default "auto")

Example

You can find example file of *.osm.pbf file in nested child /example_data.

If you want WKT format for output geometry and auto agent type:

osm2ch --file example_data/moscow_center_reduced.osm.pbf --out graph.csv --geomf wkt --agents auto

If you want GeoJSON format for output geometry and auto agent type:

osm2ch --file example_data/moscow_center_reduced.osm.pbf --out graph.csv --geomf geojson --agents auto

After that 3 files will be created: graph.csv (edges), graph_vertices.csv, graph_shortcuts.csv.

Output format

Edges CSV

Header: from_vertex_id;to_vertex_id;length_meters;free_speed;geom;was_one_way;edge_id;osm_way_from;osm_way_to;osm_way_from_source_node;osm_way_from_target_node;osm_way_to_source_node;osm_way_to_target_node;macro_node_from_source;macro_node_from_target;macro_node_to_source;macro_node_to_target

Column	Type	Description
from_vertex_id	int64	Source vertex in edge-expanded graph (= source macro link ID)
to_vertex_id	int64	Target vertex in edge-expanded graph (= target macro link ID)
length_meters	float64	Length of the expanded edge in meters
free_speed	float64	Free-flow speed in km/h
geom	string	Geometry (LineString) in WKT or GeoJSON format
was_one_way	bool	True if the source OSM way was one-way
edge_id	int64	ID of the expanded edge
osm_way_from	int64	OSM Way ID of the source (income) macro link
osm_way_to	int64	OSM Way ID of the target (outcome) macro link
osm_way_from_source_node	int64	OSM Node ID at the start of the source macro link
osm_way_from_target_node	int64	OSM Node ID at the end of the source macro link
osm_way_to_source_node	int64	OSM Node ID at the start of the target macro link
osm_way_to_target_node	int64	OSM Node ID at the end of the target macro link
macro_node_from_source	int	GMNS macro node ID at the start of the source macro link
macro_node_from_target	int	GMNS macro node ID at the end of the source macro link
macro_node_to_source	int	GMNS macro node ID at the start of the target macro link
macro_node_to_target	int	GMNS macro node ID at the end of the target macro link

Vertices CSV

Header: vertex_id;order_pos;importance;geom

Column	Type	Description
vertex_id	int64	Vertex ID (= macro link ID)
order_pos	int	Order position in contraction hierarchies
importance	int	Importance of vertex in contraction hierarchies
geom	string	Geometry (Point) in WKT or GeoJSON format

Shortcuts CSV

Header: from_vertex_id;to_vertex_id;weight;via_vertex_id

Column	Type	Description
from_vertex_id	int64	Source vertex
to_vertex_id	int64	Target vertex
weight	float64	Shortcut cost in seconds (travel time)
via_vertex_id	int64	Intermediate vertex

Contraction hierarchies are built using travel time (seconds) as the cost metric: length_meters / (free_speed_kmh / 3.6). Shortcut costs are also in seconds.

If you need route distance in meters (e.g. for map matching transition probabilities), sum up length_meters of each edge along the CH path.

Now you can use this graph in contraction hierarchies library.

Dependencies

• osm2gmns - OSM to GMNS macroscopic network + movements
• go-gmns - GMNS data structures and generators
• ch - Contraction hierarchies
• paulmach/osm - OSM data types
• paulmach/orb - Geometry types

License

• Please see here