Corrected numresolution calculation #1673.

diff --git a/ChangeLog b/ChangeLog
index 3b6e5c733677536cefd3f212fc702a8ffd52777f..2e7fb17f890483bf9c79b2c024fad84f74c5481e 100644 (file)
--- 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 279f659cb3022fcc3d980b5fdf5bae1acf98bfd6..985db7f1094c1915acc7437baa7377be64ee0ba6 100644 (file)
--- 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);
 }