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geojson-minifier

geojson-minifier is a small utility that minifies GeoJSON files by encoding(delta and zigzag) geometries. Depending on data, you can shrink file size up to 2-4 times, sometimes even more. Use it to speed up load time of your web application.

Installation

Either fetch source code or install with npm:

npm install -g geojson-minifier

This will give you geojson-minifier command.

CLI

Use geojson-minifier from command line passing -o, -f and -p parameters(operation, input file, decimal precision). When dealing with coordinate systems where decimal precision is important, like WGS84, use parameter -p to specify number of decimal places that utility should retain. The default is 0.

geojson-minifier -o pack -f <filename> -p 6

This will create minified version <filename>.packed in the same folder as input file. To unpack use following:

geojson-minifier -o unpack -f <filename>.packed -p 6

API

If you want to integrate geojson-minifier into existing application you can use 2 methods that API exposes - pack and unpack:

var GeojsonMinifier = require('geojson-minifier');
var minifier = new GeojsonMinifier({ precision: 6 });

var packed = minifier.pack(<geojson-object>);
var unpacked = minifier.unpack(<geojson-object>);