From f1b0dc6f04ac0c14a9013167b2d8150877a32e17 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Thu, 22 Sep 2022 14:04:37 +0200
Subject: [PATCH] Tweak the heuristic that handles JPEG images with a wildly
 incorrect SOF (Start of Frame) `scanLines` parameter (issue 15492)

---
 src/core/jpg.js               | 6 +++---
 test/pdfs/issue15492.pdf.link | 1 +
 test/test_manifest.json       | 8 ++++++++
 3 files changed, 12 insertions(+), 3 deletions(-)
 create mode 100644 test/pdfs/issue15492.pdf.link

diff --git a/src/core/jpg.js b/src/core/jpg.js
index 6b53131cc..0bb3dce45 100644
--- a/src/core/jpg.js
+++ b/src/core/jpg.js
@@ -163,11 +163,11 @@ function decodeScan(
             // Heuristic to attempt to handle corrupt JPEG images with too
             // large `scanLines` parameter, by falling back to the currently
             // parsed number of scanLines when it's at least (approximately)
-            // one order of magnitude smaller than expected (fixes
-            // issue10880.pdf and issue10989.pdf).
+            // one "half" order of magnitude smaller than expected (fixes
+            // issue10880.pdf, issue10989.pdf, issue15492.pdf).
             if (
               maybeScanLines > 0 &&
-              Math.round(frame.scanLines / maybeScanLines) >= 10
+              Math.round(frame.scanLines / maybeScanLines) >= 5
             ) {
               throw new DNLMarkerError(
                 "Found EOI marker (0xFFD9) while parsing scan data, " +
diff --git a/test/pdfs/issue15492.pdf.link b/test/pdfs/issue15492.pdf.link
new file mode 100644
index 000000000..3dba7ce8e
--- /dev/null
+++ b/test/pdfs/issue15492.pdf.link
@@ -0,0 +1 @@
+https://github.com/mozilla/pdf.js/files/9624549/EP_Kandzetovic.pdf
diff --git a/test/test_manifest.json b/test/test_manifest.json
index 83936caa2..e566f083f 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -5166,6 +5166,14 @@
        "lastPage": 1,
        "type": "eq"
     },
+    {  "id": "issue15492",
+       "file": "pdfs/issue15492.pdf",
+       "md5": "968d36ef340852a4c0e6fa22ced96798",
+       "rounds": 1,
+       "link": true,
+       "lastPage": 1,
+       "type": "eq"
+    },
     {  "id": "issue9650",
        "file": "pdfs/issue9650.pdf",
        "md5": "20d50bda6b1080b6d9088811299c791e",