From 06dbf4fc110d7415d7909a6d4e769852d30d51b6 Mon Sep 17 00:00:00 2001
From: Rdataflow <waldgis@bafu.admin.ch>
Date: Wed, 8 Jan 2025 17:53:11 +0100
Subject: [PATCH] feat: add zstd compression

Closes: https://github.com/geotiffjs/geotiff.js/issues/372
---
 src/compression/index.js |  7 +++++++
 src/compression/zstd.js  | 10 ++++++++++
 2 files changed, 17 insertions(+)
 create mode 100644 src/compression/zstd.js

diff --git a/src/compression/index.js b/src/compression/index.js
index 81c53b01..7a1b51e7 100644
--- a/src/compression/index.js
+++ b/src/compression/index.js
@@ -32,4 +32,11 @@ addDecoder(34887, () => import('./lerc.js')
   })
   .then((m) => m.default),
 );
+addDecoder(50000, () => import('./zstd.js')
+  .then(async (m) => {
+    await m.zstd.init();
+    return m;
+  })
+  .then((m) => m.default),
+);
 addDecoder(50001, () => import('./webimage.js').then((m) => m.default));
diff --git a/src/compression/zstd.js b/src/compression/zstd.js
new file mode 100644
index 00000000..09d7730e
--- /dev/null
+++ b/src/compression/zstd.js
@@ -0,0 +1,10 @@
+import { ZSTDDecoder } from 'zstddec';
+import BaseDecoder from './basedecoder.js';
+
+export const zstd = new ZSTDDecoder();
+
+export default class ZstdDecoder extends BaseDecoder {
+  decodeBlock(buffer) {
+    return zstd.decode(new Uint8Array(buffer)).buffer;
+  }
+}