Added LERC_ZSTD decompression

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v1
       with:
-        node-version: 14.x
+        node-version: 20.x
     - run: npm ci
     - run: npm run build
     - run: npm test

package.json

@@ -88,7 +88,8 @@
     "parse-headers": "^2.0.2",
     "quick-lru": "^6.1.1",
     "web-worker": "^1.2.0",
-    "xml-utils": "^1.0.2"
+    "xml-utils": "^1.0.2",
+    "zstddec": "^0.1.0"
   },
   "devDependencies": {
     "@babel/core": "^7.8.7",
@@ -107,7 +108,6 @@
     "express": "^4.17.1",
     "finalhandler": "^1.1.2",
     "fs-extra": "^7.0.1",
-    "isomorphic-fetch": "^2.2.1",
     "jsdoc": "^3.6.4",
     "jsdoc-plugin-intersection": "^1.0.4",
     "jsdoc-plugin-typescript": "^2.0.6",

scripts/serialize-workers.cjs

@@ -48,7 +48,7 @@ async function build(input, { minify = true } = {}) {
         import Worker from 'web-worker';
         export function create() {
           const source = ${JSON.stringify(code)};
-          return new Worker(typeof Blob === 'undefined'
+          return new Worker(typeof Buffer !== 'undefined' 
             ? 'data:application/javascript;base64,' + Buffer.from(source, 'binary').toString('base64')
             : URL.createObjectURL(new Blob([source], {type: 'application/javascript'})));
         }

src/compression/index.js

@@ -25,5 +25,11 @@ addDecoder(6, () => {
 addDecoder(7, () => import('./jpeg.js').then((m) => m.default));
 addDecoder([8, 32946], () => import('./deflate.js').then((m) => m.default));
 addDecoder(32773, () => import('./packbits.js').then((m) => m.default));
-addDecoder(34887, () => import('./lerc.js').then((m) => m.default));
+addDecoder(34887, () => import('./lerc.js')
+  .then(async (m) => {
+    await m.zstd.init();
+    return m;
+  })
+  .then((m) => m.default),
+);
 addDecoder(50001, () => import('./webimage.js').then((m) => m.default));

src/compression/lerc.js

@@ -1,8 +1,11 @@
 import { inflate } from 'pako';
 import Lerc from 'lerc';
+import { ZSTDDecoder } from 'zstddec';
 import BaseDecoder from './basedecoder.js';
 import { LercParameters, LercAddCompression } from '../globals.js';
 
+export const zstd = new ZSTDDecoder();
+
 export default class LercDecoder extends BaseDecoder {
   constructor(fileDirectory) {
     super();
@@ -20,6 +23,9 @@ export default class LercDecoder extends BaseDecoder {
       case LercAddCompression.Deflate:
         buffer = inflate(new Uint8Array(buffer)).buffer; // eslint-disable-line no-param-reassign, prefer-destructuring
         break;
+      case LercAddCompression.Zstandard:
+        buffer = zstd.decode(new Uint8Array(buffer)).buffer; // eslint-disable-line no-param-reassign, prefer-destructuring
+        break;
       default:
         throw new Error(`Unsupported LERC additional compression method identifier: ${this.addCompression}`);
     }

src/globals.js

@@ -235,6 +235,7 @@ export const LercParameters = {
 export const LercAddCompression = {
   None: 0,
   Deflate: 1,
+  Zstandard: 2,
 };
 
 export const geoKeyNames = {

test/data/setup_data.sh

@@ -25,9 +25,11 @@ gdal_translate -of GTiff -co BIGTIFF=YES stripped.tiff bigtiff.tiff
 gdal_translate -of GTiff -co COMPRESS=LERC -co MAX_Z_ERROR=1000 stripped.tiff lerc.tiff
 gdal_translate -of GTiff -co COMPRESS=LERC -co MAX_Z_ERROR=1000 -co INTERLEAVE=BAND stripped.tiff lerc_interleave.tiff
 gdal_translate -of GTiff -co COMPRESS=LERC_DEFLATE -co MAX_Z_ERROR=1000 stripped.tiff lerc_deflate.tiff
+gdal_translate -of GTiff -co COMPRESS=LERC_ZSTD -co MAX_Z_ERROR=1000 stripped.tiff lerc_zstd.tiff
 gdal_translate -of GTiff -ot Float32 -co COMPRESS=LERC -co MAX_Z_ERROR=1000 stripped.tiff float32lerc.tiff
 gdal_translate -of GTiff -ot Float32 -co COMPRESS=LERC -co MAX_Z_ERROR=1000 -co INTERLEAVE=BAND stripped.tiff float32lerc_interleave.tiff
 gdal_translate -of GTiff -ot Float32 -co COMPRESS=LERC_DEFLATE -co MAX_Z_ERROR=1000 stripped.tiff float32lerc_deflate.tiff
+gdal_translate -of GTiff -ot Float32 -co COMPRESS=LERC_ZSTD -co MAX_Z_ERROR=1000 stripped.tiff float32lerc_zstd.tiff
 
 gdal_translate -of COG initial.tiff cog.tiff
 

test/geotiff.spec.js

@@ -4,7 +4,6 @@ import { expect } from 'chai';
 import http from 'http';
 import serveStatic from 'serve-static';
 import finalhandler from 'finalhandler';
-import 'isomorphic-fetch';
 import AbortController from 'node-abort-controller';
 import { dirname } from 'path';
 
@@ -243,6 +242,11 @@ describe('GeoTIFF', () => {
     await performTiffTests(tiff, 539, 448, 15, Uint16Array);
   });
 
+  it('should work on LERC Zstandard compressed tiffs', async () => {
+    const tiff = await GeoTIFF.fromSource(createSource('lerc_zstd.tiff'));
+    await performTiffTests(tiff, 539, 448, 15, Uint16Array);
+  });
+
   it('should work on Float32 and LERC compressed tiffs', async () => {
     const tiff = await GeoTIFF.fromSource(createSource('float32lerc.tiff'));
     await performTiffTests(tiff, 539, 448, 15, Float32Array);
@@ -258,6 +262,11 @@ describe('GeoTIFF', () => {
     await performTiffTests(tiff, 539, 448, 15, Float32Array);
   });
 
+  it('should work on Float32 and LERC Zstandard compressed tiffs', async () => {
+    const tiff = await GeoTIFF.fromSource(createSource('float32lerc_zstd.tiff'));
+    await performTiffTests(tiff, 539, 448, 15, Float32Array);
+  });
+
   it('should work with worker pool', async () => {
     const testPool = new Pool();
     const tiff = await GeoTIFF.fromSource(createSource('nasa_raster.tiff'));

test/source.js

@@ -1,6 +1,5 @@
 /* eslint-disable global-require, no-unused-expressions */
 import isNode from 'detect-node';
-import 'isomorphic-fetch';
 import { expect } from 'chai';
 
 import { makeFetchSource } from '../src/source/remote.js';

tsconfig.json

@@ -1,7 +1,7 @@
 {
   "compilerOptions": {
     "target": "ES5",
-    "lib": ["ES2020"],
+    "lib": ["ES2020", "DOM"],
     "allowJs": true,
     "declaration": true,
     "declarationMap": true,