From: dirk <dirk@git.imagemagick.org>
Date: Sat, 3 Sep 2016 19:08:33 +0000 (+0200)
Subject: CopyCompositeOp should set the alpha channel to opaque if the source image has no... 
X-Git-Tag: 7.0.3-0~3
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=65d195e5b3cdbf4a62270f403597af41a5d4b1b3;p=imagemagick

CopyCompositeOp should set the alpha channel to opaque if the source image has no alpha channel.
---

diff --git a/MagickCore/composite.c b/MagickCore/composite.c
index 8e70a7f95..f9945b2c9 100644
--- a/MagickCore/composite.c
+++ b/MagickCore/composite.c
@@ -641,16 +641,18 @@ MagickExport MagickBooleanType CompositeImage(Image *image,
               q+=GetPixelChannels(image);
               continue;
             }
-          for (i=0; i < (ssize_t) GetPixelChannels(source_image); i++)
+          for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
           {
-            PixelChannel channel=GetPixelChannelChannel(source_image,i);
+            PixelChannel channel=GetPixelChannelChannel(image,i);
+            PixelTrait traits=GetPixelChannelTraits(image,channel);
             PixelTrait source_traits=GetPixelChannelTraits(source_image,
               channel);
-            PixelTrait traits=GetPixelChannelTraits(image,channel);
-            if ((traits == UndefinedPixelTrait) ||
-                (source_traits == UndefinedPixelTrait))
+            if (traits == UndefinedPixelTrait)
               continue;
-            SetPixelChannel(image,channel,p[i],q);
+            if (source_traits != UndefinedPixelTrait)
+              SetPixelChannel(image,channel,p[i],q);
+            else if (channel == AlphaPixelChannel)
+              SetPixelChannel(image,channel,OpaqueAlpha,q);
           }
           p+=GetPixelChannels(source_image);
           q+=GetPixelChannels(image);