From 310101b45d8cddb6eceb4369fde7db59cd372865 Mon Sep 17 00:00:00 2001
From: Dirk Lemstra <dirk@lemstra.org>
Date: Fri, 23 Aug 2019 10:59:46 +0200
Subject: [PATCH] Corrected numresolution calculation #1673.

---
 ChangeLog    | 2 ++
 coders/jp2.c | 3 +--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 3b6e5c733..2e7fb17f8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@
 2019-08-23  7.0.8-62 Dirk Lemstra <dirk@lem.....org>
   * Added option to limit the maximum point size with -define
     caption:max-pointsize=pointsize.
+  * Corrected JP2 numresolution calculation (reference:
+    https://github.com/ImageMagick/ImageMagick/issues/1673)
 
 2019-08-19  7.0.8-62 Cristy  <quetzlzacatenango@image...>
   * Conditionally compile call to AcquireCLocale() (reference
diff --git a/coders/jp2.c b/coders/jp2.c
index 279f659cb..985db7f10 100644
--- a/coders/jp2.c
+++ b/coders/jp2.c
@@ -783,8 +783,7 @@ static inline int CalculateNumResolutions(size_t width,size_t height)
     i;
 
   for (i=1; i < 6; i++)
-    if ((((size_t) 1UL << (i+2)) > width) &&
-        (((size_t) 1UL << (i+2)) > height))
+    if ((width < ((size_t) 1UL << i)) || (height < ((size_t) 1UL << i)))
       break;
   return(i);
 }
-- 
2.40.0