From 1021b7cc8a8a1fae15a3824a1026acdf7466de8f Mon Sep 17 00:00:00 2001
From: Alexander Ebert <ebert@woltlab.com>
Date: Fri, 17 Jan 2025 17:37:27 +0100
Subject: [PATCH] Fix copying of JPEG EXIF into WebP

---
 ts/WoltLabSuite/Core/Image/WebP.ts                        | 5 +++++
 wcfsetup/install/files/js/WoltLabSuite/Core/Image/WebP.js | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/ts/WoltLabSuite/Core/Image/WebP.ts b/ts/WoltLabSuite/Core/Image/WebP.ts
index 46ede94a4c..6f23f8476b 100644
--- a/ts/WoltLabSuite/Core/Image/WebP.ts
+++ b/ts/WoltLabSuite/Core/Image/WebP.ts
@@ -93,6 +93,11 @@ class WebP {
   }
 
   exportWithExif(exif: Exif): Uint8Array {
+    // The EXIF might originate from a JPEG thus we need to strip the header.
+    if (exif[0] === 0xff && exif[1] === 0xe1 && exif[2] === 0xc3 && exif[3] === 0xef) {
+      exif = exif.slice(10);
+    }
+
     const iccp = this.#getChunk(ChunkHeader.ICCP);
     const anim = this.#getChunk(ChunkHeader.ANIM);
 
diff --git a/wcfsetup/install/files/js/WoltLabSuite/Core/Image/WebP.js b/wcfsetup/install/files/js/WoltLabSuite/Core/Image/WebP.js
index 90af55147d..7d389c95f5 100644
--- a/wcfsetup/install/files/js/WoltLabSuite/Core/Image/WebP.js
+++ b/wcfsetup/install/files/js/WoltLabSuite/Core/Image/WebP.js
@@ -60,6 +60,10 @@ define(["require", "exports"], function (require, exports) {
             return undefined;
         }
         exportWithExif(exif) {
+            // The EXIF might originate from a JPEG thus we need to strip the header.
+            if (exif[0] === 0xff && exif[1] === 0xe1 && exif[2] === 0xc3 && exif[3] === 0xef) {
+                exif = exif.slice(10);
+            }
             const iccp = this.#getChunk("ICCP" /* ChunkHeader.ICCP */);
             const anim = this.#getChunk("ANIM" /* ChunkHeader.ANIM */);
             const imageData = [];