Plugins

This section describes optional plugins possibilities of CARS.

Note

Work in progress !

Shareloc Geometry plugin

By default, the geometry functions in CARS are run through OTB.

Another geometry library called Shareloc is installed with CARS and can be configured to be used as another option.

To use Shareloc library, CARS input configuration should be defined as :

{
  "inputs": {
    "sensors": {
      "one": {
        "image": "img1.tif",
        "geomodel": "img1.geom",
        "geomodel_type": "RPC"
      },
      "two": {
        "image": "img2.tif",
        "geomodel": "img2.geom",
        "geomodel_type": "RPC"
      }
    },
    "pairing": [["one", "two"]],
    "initial_elevation": "path/to/srtm_file"
  },
  "output": {
    "out_dir": "outresults"
  },
  "applications": {
    "grid_generation": {
      "method": "epipolar",
      "geometry_loader": "SharelocGeometry"
    },
    "triangulation": {
      "method": "line_of_sight_intersection",
      "geometry_loader": "SharelocGeometry"
    }
  }
}

The standards parts are described in CARS Configuration.

The particularities in the configuration file are:

• geomodel: field contain the paths to the geometric model files related to img1 and img2 respectively. These files have to be supported by the Shareloc library.

• geomodel_type: Depending on the nature of the geometric models indicated above, this field as to be defined as RPC or GRID. By default, “RPC”

• initial_elevation: Shareloc must have a file, typically a SRTM tile (and not a directory as OTB default configuration !!)

• geometry_loader: field in grid_generation and triangulation applications configured to “SharelocGeometry” to use Shareloc plugin.

Note

This library is foreseen to replace OTB default in CARS for maintenance and installation ease. Be aware that geometric models must therefore be opened by shareloc directly in this case, and supported sensors may evolve.