2.1. mola-sm-georeferencing: optimal geo-referencing
This program finds the optimal geo-referencing parameters for a map.
First, build a simple-map from a dataset or a live robot as described in Tutorial: build a map.
Make sure of having a GPS (GNSS) sensor source emitting observations, and that they were captured
by MOLA-LO (see the corresponding variable in the LO pipeline).
Then, build the corresponding metric map by applying a metric map generation pipeline (see [BC25])
or this step in the tutorial:
# Build metric map (mm) from simplemap (sm):
sm2mm -i datasetWithGPS.simplemap -o myMap.mm -p sm2mm_pipeline.yaml
Now, to find out the optimized map-to-ENU transformation and write it into the
map file, use:
# georeference it:
mola-sm-georeferencing -i datasetWithGPS.simplemap --write-into myMap.mm
Alternatively, the georeferenciation metadata can be also stored, independently of a metric map,
in an independent file with:
# georeference it:
mola-sm-georeferencing -i datasetWithGPS.simplemap --output myMap.georef
USAGE:
mola-sm-georeferencing [-v <INFO>] [-l <foobar.so>]
[--horizontality-sigma <1.0>] [-o <map.georef>]
[--write-into <map.mm>] -i <map.simplemap> [--]
[--version] [-h]
Where:
-v <INFO>, --verbosity <INFO>
Verbosity level: ERROR|WARN|INFO|DEBUG (Default: INFO)
-l <foobar.so>, --load-plugins <foobar.so>
One or more (comma separated) *.so files to load as plugins, e.g.
defining new CMetricMap classes
--horizontality-sigma <1.0>
For short trajectories (not >10x the GPS uncertainty), this helps to
avoid degeneracy.
-o <map.georef>, --output <map.georef>
Write the obtained georeferencing metadata to a .georef file
--write-into <map.mm>
An existing .mm file in which to write the georeferencing metadata
-i <map.simplemap>, --input <map.simplemap>
(required) Input .simplemap file
--, --ignore_rest
Ignores the rest of the labeled arguments following this flag.
--version
Displays version information and exits.
-h, --help
Displays usage information and exits.
2.2. mola-trajectory-georef: georeferenced trajectories
Once you already have a trajectory file in the local map frame of reference,
for example, as generated by MOLA-LO in TUM format,
and after georeferencing the generated map as shown above,
you can use the CLI tool mola-trajectory-georef to convert it into geodetic coordinates,
for example in KML format suitable for visualization in Google Earth.
USAGE:
mola-trajectory-georef -o <path.kml> -t <traj.tum> [-g <map.georef>]
[-m <map.mm>] [--] [--version] [-h]
Where:
-o <path.kml>, --output <path.kml>
(required) The name of the google earth kml file to write to
-t <traj.tum>, --trajectory <traj.tum>
(required) Input .tum trajectory, in map local coordinates
-g <map.georef>, --geo-ref <map.georef>
Input .georef file with georef info
-m <map.mm>, --map <map.mm>
Input .mm map with georef info
--, --ignore_rest
Ignores the rest of the labeled arguments following this flag.
--version
Displays version information and exits.
-h, --help
Displays usage information and exits.
2.3. mola-mm-add-geodetic: add geodetic coordinates to point clouds
Once you have a georeferenced metric map (*.mm file), you can use the CLI tool
mola-mm-add-geodetic to enrich point cloud layers with geodetic coordinates
(latitude, longitude, altitude in WGS84). This adds three new double-precision fields
to each point in CGenericPointsMap-based layers, enabling direct use of geographic
coordinates in subsequent analysis or export to GIS applications.
The tool automatically handles the coordinate transformation from the map’s local frame
to geodetic coordinates using either embedded georeferencing metadata or an external
georeferencing file.
The output metric map will contain the same structure as the input, but point cloud
layers (CGenericPointsMap-based) will have three additional double-precision fields:
latitude: WGS84 latitude in decimal degrees
longitude: WGS84 longitude in decimal degrees
altitude: WGS84 ellipsoidal height in meters
These fields can then be exported to text or PLY format using mm2txt or mm2ply
respectively, with the --export-fields option to include the geodetic coordinates.
For example, to export only coordinates and geodetic information:
mm2txt output.mm --export-fields "x,y,z,latitude,longitude,altitude"
USAGE:
mola-mm-add-geodetic -i <input.mm> -o <output.mm> [-g <map.georef>]
[-l <layerName>] ... [-p <foobar.so>] [-v] [--]
[--version] [-h]
Where:
-i <input.mm>, --input <input.mm>
(required) Input metric map file (*.mm)
-o <output.mm>, --output <output.mm>
(required) Output metric map file (*.mm) with geodetic coordinates
added
-g <map.georef>, --georef <map.georef>
Optional geo-referencing file (*.georef or *.yaml) to use if the
input map does not have embedded georeferencing information
-l <layerName>, --layer <layerName> (accepted multiple times)
Layer(s) to process. If not provided, all CGenericPointsMap layers
will be processed. This argument can appear multiple times.
-p <foobar.so>, --load-plugins <foobar.so>
One or more (comma separated) *.so files to load as plugins
-v, --verbose
Enable verbose output with progress information
--, --ignore_rest
Ignores the rest of the labeled arguments following this flag.
--version
Displays version information and exits.
-h, --help
Displays usage information and exits.
Basic usage with embedded georeferencing:
mola-mm-add-geodetic -i input.mm -o output.mm
Using an external georeferencing file:
mola-mm-add-geodetic -i input.mm -o output.mm -g map.georef
Process specific layers only:
mola-mm-add-geodetic -i input.mm -o output.mm -l raw -l filtered
Verbose mode for large datasets:
mola-mm-add-geodetic -i input.mm -o output.mm -v
