From 39e36368e7d2206cda4bb9cc34973b0b01d52147 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Milo=C5=A1=20Komar=C4=8Devi=C4=87?=
 <4973094+kmilos@users.noreply.github.com>
Date: Wed, 7 Jul 2021 09:38:06 +0200
Subject: [PATCH] Ensure TIFF RowsPerStrip is multiple of 8 for JPEG
 compression

---
 src/PIL/TiffImagePlugin.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/PIL/TiffImagePlugin.py b/src/PIL/TiffImagePlugin.py
index a5e2bb53d..3f34cc9ac 100644
--- a/src/PIL/TiffImagePlugin.py
+++ b/src/PIL/TiffImagePlugin.py
@@ -1577,6 +1577,9 @@ def _save(im, fp, filename):
     # aim for 64 KB strips when using libtiff writer
     if libtiff:
         rows_per_strip = min((2 ** 16 + stride - 1) // stride, im.size[1])
+        # JPEG encoder expects multiple of 8 rows
+        if compression == "jpeg":
+            rows_per_strip = min(((rows_per_strip + 7) // 8) * 8, im.size[1])
     else:
         rows_per_strip = im.size[1]
     strip_byte_counts = stride * rows_per_strip