From: Cristy <urban-warrior@imagemagick.org>
Date: Tue, 28 Feb 2017 01:41:33 +0000 (-0500)
Subject: ...
X-Git-Tag: 7.0.5-1~12
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=2cc7345d8eb326a3dd3a714b9de64d36db2e8ab1;p=imagemagick

...
---

diff --git a/MagickCore/compare.c b/MagickCore/compare.c
index 5cdbd89e7..1b7c32e8e 100644
--- a/MagickCore/compare.c
+++ b/MagickCore/compare.c
@@ -1212,13 +1212,10 @@ static MagickBooleanType GetPeakSignalToNoiseRatio(const Image *image,
 
   status=GetMeanSquaredDistortion(image,reconstruct_image,distortion,exception);
   for (i=0; i <= MaxPixelChannels; i++)
-  {
-    double
-      gamma;
-
-    gamma=PerceptibleReciprocal(sqrt(distortion[i]));
-    distortion[i]=20.0*MagickLog10(gamma);
-  }
+    if (fabs(distortion[i]) < MagickEpsilon)
+      distortion[i]=INFINITY;
+    else
+      distortion[i]=20.0*MagickLog10(1.0/sqrt(distortion[i]));
   return(status);
 }
 
diff --git a/MagickCore/magick-type.h b/MagickCore/magick-type.h
index a7b76d297..059206775 100644
--- a/MagickCore/magick-type.h
+++ b/MagickCore/magick-type.h
@@ -167,6 +167,9 @@ typedef enum
 #else
 #  define IsNaN(a) (a != a)
 #endif
+#if !defined(INFINITY)
+#  define INFINITY (log(0))
+#endif
 
 typedef struct _BlobInfo BlobInfo;