From: cristy <urban-warrior@git.imagemagick.org>
Date: Thu, 22 Oct 2009 23:59:52 +0000 (+0000)
Subject: (no commit message)
X-Git-Tag: 7.0.1-0~10479
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=46f7d71a4b5e8e208143d65eea9571050603126b;p=imagemagick

---

diff --git a/ChangeLog b/ChangeLog
index ca5dd14ad..dab7b0587 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,7 @@
 2009-10-18  6.5.7-1 Cristy  <quetzlzacatenango@image...>
   * Alpha blending is not required for ScaleImage().
   * Guassian noise operator is not longer discontinuous.
+  * Correct hue computation for the HSB colorspace.
 
 2009-10-14  6.5.7-0 Pino Toscano  <pino@kde...>
   * ImageMagick fails to build in GNU/HURD due to absence of PATH_MAX.
diff --git a/magick/gem.c b/magick/gem.c
index f0cd3467e..747ba0762 100644
--- a/magick/gem.c
+++ b/magick/gem.c
@@ -372,16 +372,20 @@ MagickExport void ConvertRGBToHSB(const Quantum red,const Quantum green,
   *brightness=(double) (QuantumScale*max);
   if (delta == 0.0)
     return;
-  if ((MagickRealType) red == max)
-    *hue=(double) ((green-(MagickRealType) blue)/delta);
+  if (red == max)
+    *hue=((((max-blue)/6.0)+(delta/2.0))-(((max-green)/6.0)+(delta/2.0)))/delta;
   else
-    if ((MagickRealType) green == max)
-      *hue=(double) (2.0+(blue-(MagickRealType) red)/delta);
+    if (green == max)
+      *hue=(1.0/3.0)+((((max-red)/6.0)+(delta/2.0))-(((max-blue)/6.0)+
+        (delta/2.0)))/delta;
     else
-      *hue=(double) (4.0+(red-(MagickRealType) green)/delta);
-  *hue/=6.0;
+      if (blue == max)
+        *hue=(2.0/3.0)+((((max-green)/6.0)+(delta/2.0))-(((max-red)/6.0)+
+          (delta/2.0)))/delta;
   if (*hue < 0.0)
     *hue+=1.0;
+  if (*hue > 1.0)
+    *hue-=1.0;
 }
 
 /*