@wtchen/gdal3.js

gdal3.js - Gdal compiled to JavaScript

gdal3.js is a port of Gdal applications (gdal_translate, ogr2ogr, gdal_rasterize, gdalwarp, gdaltransform) to Webassembly. It allows you to convert raster and vector geospatial data to various formats and coordinate systems.

gdal3.js uses emscripten to compile Gdal, proj, geos, spatialite, sqlite, geotiff, tiff, webp, jpeg, expat and zlib to webassembly.

If you are building a native application in JavaScript (using Electron for instance), or are working in node.js, you will likely prefer to use a native binding of Gdal to JavaScript. A native binding will be faster because it will run native code.

gdal3.js GUI

gdal3.js GUI is a web application that provides a gui to gdal_translate, ogr2ogr and gdal_rasterize applications to be used online. Uses gdal3.js in the background. It runs on the browser and files are converted on the client side.

https://gdal3.js.org

Supported Formats

Raster

Read & Write
AAIGrid, ADRG, ARG, BLX, BMP, BT, BYN, CALS, CTable2, DTED, EHdr, ELAS, ENVI, ERS, FIT, GIF, GPKG, GRIB, GS7BG, GSAG, GSBG, GTX, GTiff, HF2, HFA, ILWIS, ISCE, ISIS2, ISIS3, JPEG, KMLSUPEROVERLAY, KRO, LAN, LCP, Leveller, MBTiles, MEM, MFF, MFF2, MRF, NITF, NTv2, NWT_GRD, PAux, PCIDSK, PCRaster, PDS4, PNG, PNM, R, RMF, ROI_PAC, RRASTER, RST, Rasterlite, SAGA, SGI, SIGDEM, SRTMHGT, Terragen, USGSDEM, VICAR, VRT, WEBP, WMTS, XPM, XYZ, ZMap, Zarr

Read Only
ACE2, AIG, AirSAR, BIGGIF, BSB, CAD, CEOS, COASP, COSAR, CPG, CTG, DERIVED, DIMAP, DIPEx, DOQ1, DOQ2, ECRGTOC, EIR, ESAT, ESRIC, FAST, GFF, GRASSASCIIGrid, GSC, GXF, GenBin, IRIS, ISG, JAXAPALSAR, JDEM, L1B, LOSLAS, MAP, MSGN, NDF, NGSGEOID, NWT_GRC, OGCAPI, OZI, PDS, PRF, RIK, RPFTOC, RS2, SAFE, SAR_CEOS, SDTS, SENTINEL2, SNODAS, SRP, STACIT, STACTA, TGA, TIL, TSX

Write Only
COG, PDF

Vector

Read & Write
CSV, DGN, DXF, ESRI Shapefile, FlatGeobuf, GML, GPKG, GPSBabel, GPX, GeoJSON, GeoJSONSeq, GeoRSS, Geoconcept, JML, KML, MBTiles, MVT, MapInfo File, MapML, Memory, ODS, OGR_GMT, PCIDSK, PDS4, S57, SQLite/Spatialite, VDV, VICAR, WAsP, XLSX

Read Only
AVCBin, AVCE00, CAD, EDIGEO, ESRIJSON, Idrisi, LVBAG, OGCAPI, OGR_PDS, OGR_SDTS, OGR_VRT, OSM, OpenFileGDB, SVG, SXF, TIGER, TopoJSON, UK .NTF, VFK

Write Only
PDF, PGDUMP

Guide

Installation

Script (CDN)
Note: It doesn't work with web worker.

<script type="text/javascript"
    src="https://cdn.jsdelivr.net/npm/gdal3.js@2.4.0/dist/package/gdal3.js"
    integrity="sha384-XlqVvSG4V8zz8Kdw95OpRdsWyJnWE5QUZy++BeAIEVb+f2n5RM7jdbZh5lm0pHWk"
    crossorigin="anonymous"
></script>

initGdalJs({ path: 'https://cdn.jsdelivr.net/npm/gdal3.js@2.4.0/dist/package', useWorker: false }).then((Gdal) => {});

Example: https://github.com/bugra9/gdal3.js/tree/master/apps/example-browser

Script (Local)

<script type="text/javascript" src="gdal3.js"></script>

initGdalJs().then((Gdal) => {});

Example: https://github.com/bugra9/gdal3.js/tree/master/apps/example-browser-worker

ES Module

<script type="module">
    import 'gdal3.js'

    initGdalJs().then((Gdal) => {});
</script>

Example: https://github.com/bugra9/gdal3.js/tree/master/apps/example-module-browser-worker
Example: https://github.com/bugra9/gdal3.js/tree/master/apps/example-module-browser

Builder such as Webpack (Vue, React, Angular, ...)

yarn add gdal3.js
# or
npm install gdal3.js

import initGdalJs from 'gdal3.js';

initGdalJs({ path: 'static' }).then((Gdal) => {});

plugins: [
    new CopyWebpackPlugin({
        patterns: [
            { from: '../node_modules/gdal3.js/dist/package/gdal3WebAssembly.wasm', to: 'static' },
            { from: '../node_modules/gdal3.js/dist/package/gdal3WebAssembly.data', to: 'static' }
        ]
    })
]

Full working example: https://github.com/bugra9/gdal3.js/blob/master/apps/app-gui/src/App.vue

Vite + Vue3

yarn add gdal3.js
# or
npm install gdal3.js

<script setup>
import { ref } from 'vue'
import workerUrl from 'gdal3.js/dist/package/gdal3.js?url'
import dataUrl from 'gdal3.js/dist/package/gdal3WebAssembly.data?url'
import wasmUrl from 'gdal3.js/dist/package/gdal3WebAssembly.wasm?url'
import initGdalJs from 'gdal3.js';

const paths = {
  wasm: wasmUrl,
  data: dataUrl,
  js: workerUrl,
};

const count = ref(0);
initGdalJs({paths}).then((Gdal) => {
    count.value = Object.keys(Gdal.drivers.raster).length + Object.keys(Gdal.drivers.vector).length;
});
</script>

<template>
  <div>Number of drivers: {{ count }}</div>
</template>

Node

yarn add gdal3.js
# or
npm install gdal3.js

const initGdalJs = require('gdal3.js/node');

initGdalJs().then((Gdal) => {});

Example: https://github.com/bugra9/gdal3.js/blob/master/apps/example-node/index.js

Basic Usage

const Gdal = await initGdalJs();

const files = ['a.mbtiles', 'b.tif']; // [Vector, Raster]
const result = await Gdal.open(files); // https://gdal3.js.org/docs/module-f_open.html
const mbTilesDataset = result.datasets[0];
const tifDataset = result.datasets[1];


/* ======== Dataset Info ======== */
// https://gdal3.js.org/docs/module-f_getInfo.html
const mbTilesDatasetInfo = await Gdal.getInfo(mbTilesDataset); // Vector
const tifDatasetInfo = await Gdal.getInfo(tifDataset); // Raster


/* ======== Vector translate (mbtiles -> geojson) ======== */
const options = [ // https://gdal.org/programs/ogr2ogr.html#description
    '-f', 'GeoJSON',
    '-t_srs', 'EPSG:4326'
];
const output = await Gdal.ogr2ogr(mbTilesDataset, options); // https://gdal3.js.org/docs/module-a_ogr2ogr.html
const bytes = await Gdal.getFileBytes(output); // https://gdal3.js.org/docs/module-f_getFileBytes.html


/* ======== Raster translate (tif -> png) ======== */
const options = [ // https://gdal.org/programs/gdal_translate.html#description
    '-of', 'PNG'
];
const output = await Gdal.gdal_translate(tifDataset, options); // https://gdal3.js.org/docs/module-a_gdal_translate.html
const bytes = await Gdal.getFileBytes(output); // https://gdal3.js.org/docs/module-f_getFileBytes.html


/* ======== Rasterize (mbtiles -> tif) ======== */
const options = [ // https://gdal.org/programs/gdal_rasterize.html#description
    '-of', 'GTiff',
    '-co', 'alpha=yes'
];
const output = await Gdal.gdal_rasterize(mbTilesDataset, options); // https://gdal3.js.org/docs/module-a_gdal_rasterize.html
const bytes = await Gdal.getFileBytes(output); // https://gdal3.js.org/docs/module-f_getFileBytes.html


/* ======== Warp (reprojection) ======== */
const options = [ // https://gdal.org/programs/gdalwarp.html#description
    '-of', 'GTiff',
    '-t_srs', 'EPSG:4326'
];
const output = await Gdal.gdalwarp(tifDataset, options); // https://gdal3.js.org/docs/module-a_gdalwarp.html
const bytes = await Gdal.getFileBytes(output); // https://gdal3.js.org/docs/module-f_getFileBytes.html


// Close all datasets. // https://gdal3.js.org/docs/module-f_close.html
Gdal.close(mbTilesDataset);
Gdal.close(tifDataset);


/* ======== Transform (Coordinate) ======== */
const coords = [
    [27.143757, 38.4247972],
];
const options = [ // https://gdal.org/programs/gdaltransform.html#description
    '-s_srs', 'EPSG:4326',
    '-t_srs', 'EPSG:3857',
    '-output_xy',
];
const newCoords = await Gdal.gdaltransform(coords, options); // https://gdal3.js.org/docs/module-a_gdaltransform.html
console.log(newCoords); // [ [ 3021629.2074563554, 4639610.441991095 ] ]

API References

https://gdal3.js.org/docs

Examples

• Full working example with worker and Vue.js -> Code, Live
• Browser with Worker -> Code, Live
• Browser without Worker -> Code, Live
• Browser with Worker (Module) -> Code, Live
• Browser without Worker (Module) -> Code, Live
• Node.js -> Code

Development

Compiling

• Install the EMSDK, as described here
• Install Sqlite3. (#31)
• Run yarn compile or make. Run make type=debug for debug version.
• Run yarn build. Run yarn build-dev for debug version.

WSL Notes

In order to compile on Windows Subsystem for Linux, you need remove all references to existing Windows paths and install the cmake package.

License

GNU Lesser General Public License v2.1 or later

See LICENSE to see the full text.

Compiled with

• Emscripten 3.1.7 (License)
• Gdal 3.5.1 (License)
• Proj 9.0.1 (License)
• Geos 3.9.2 (License)
• Spatialite 5.0.1 (License)
• Sqlite 3.38.5 (License)
• GeoTIFF 1.7.1 (License)
• Tiff 4.4.0 (License)
• WebP 1.2.0 (License)
• JPEG JFIF 9d (License)
• Expat 2.4.8 (License)
• Zlib 1.2.12 (License)
• Iconv 1.17 (License)

Inspired by

• ddohler/gdal-js
• sql-js/sql.js
• jvail/spatiasql.js
• azavea/loam