physycom / json_to_geojson

documentclass	title	author
physycomen	json_to_geojson	Di Cristina, Sinigardi

Purpose

This tool has been written to convert data to the GeoJson format from our .json structure, in order to be able to import data in our tools from the GeoJson standard.

Installation

CMake and a C++11 compatible compiler are required. To build the executable, clone the repo and then type

mkdir build ; cd build ; cmake .. ; cmake --build .

With CMake you can also deploy projects for the most common IDEs.
Contains jsoncons as a git submodule.

Usage

json_to_geojson.exe -i input.json -o output.json -f format

where input.json must be an existing and valid .json file with at least 'lat' and 'lon' keys in each element, while output.json is the name of the produced GeoJson file.

The flag -f specifies the type of the output geojson, and is one of 'p', 'm', 'fm', 'l', 'fl' (without quotes):

• 'p' for a FeatureCollection of points,
• 'm' for a simple MultiPoint,
• 'fm' for a Feature MultiPoint,
• 'l' for a simple LineString,
• 'fl' for a Feature LineString.

Input Sample

Either array-style:

[
    {
        "your_key1":"your_value",
        "your_key2":"your_value",
        "lat" : 44.498950,
        "lon" : 11.353606
    },
    {
        "your_key1":"your_value",
        "your_key2":"your_value",
        "lat" : 44.498595,
        "lon" : 11.354939
    },
    {
        "your_key1":"your_value",
        "your_key2":"your_value",
        "lat" : 44.498257,
        "lon" : 11.355894,
        "alt" : 10.0
    }
]

or object-style:

{
    "gps_record_0000001":
    {
        "your_field":"your_content",
        "lat":44.5021611,
        "lon":11.3648926
        "alt" : 56
    },
    "gps_record_0000002":
    {
        "another_field":"another_content",
        "lat":44.5021381,
        "lon":11.3648768
    }
}

Output Sample

FeatureCollection of points:

{
  "features" :
  [{
      "geometry" : {
        "coordinates" :
        [11.3648926, 44.5021611, 56],
        "type" : "Point"
      },
      "properties" : {
        "index" : 0
      },
      "type" : "Feature"
    }, {
      "geometry" : {
        "coordinates" :
        [11.3648768, 44.5021381],
        "type" : "Point"
      },
      "properties" : {
        "index" : 1
      },
      "type" : "Feature"
    }
  ],
  "type" : "FeatureCollection"
}

simple MultiPoint:

{
  "coordinates" :
  [
    [11.3648926, 44.5021611, 56],
    [11.3648768, 44.5021381]
  ],
  "type" : "MultiPoint"
}

Feature MultiPoint:

{
  "geometry" : {
    "coordinates" :
    [
      [11.3648926, 44.5021611, 56],
      [11.3648768, 44.5021381]
    ],
    "type" : "MultiPoint"
  },
  "properties" : null,
  "type" : "Feature"
}

simple LineString:

{
  "coordinates" :
  [
    [11.3648926, 44.5021611, 56],
    [11.3648768, 44.5021381]
  ],
  "type" : "LineString"
}

Feature LineString:

{
  "geometry" : {
    "coordinates" :
    [
      [11.3648926, 44.5021611, 56],
      [11.3648768, 44.5021381]
    ],
    "type" : "LineString"
  },
  "properties" : null,
  "type" : "Feature"
}

More details can be found in our technical description of the file formats published here