From: Cristy <urban-warrior@imagemagick.org>
Date: Fri, 3 Feb 2017 20:33:27 +0000 (-0500)
Subject: ...
X-Git-Tag: 7.0.4-7~2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fb9a8d5f2287eac1fbf4ef4ab09a7ed05f049d01;p=imagemagick

...
---

diff --git a/MagickCore/channel.c b/MagickCore/channel.c
index ca3811a0a..4c2decc43 100644
--- a/MagickCore/channel.c
+++ b/MagickCore/channel.c
@@ -356,6 +356,40 @@ MagickExport Image *ChannelFxImage(const Image *image,const char *expression,
           (void) SetPixelMetaChannels(destination_image,(size_t) (
             destination_channel-GetPixelChannels(destination_image)+1),
             exception);
+        if (image->colorspace != UndefinedColorspace)
+          switch (destination_channel)
+          {
+            case RedPixelChannel:
+            case GreenPixelChannel:
+            case BluePixelChannel:
+            case BlackPixelChannel:
+            case IndexPixelChannel:
+              break;
+            case AlphaPixelChannel:
+            {
+              if (image->colorspace != UndefinedColorspace)
+                destination_image->alpha_trait=BlendPixelTrait;
+              break;
+            }
+            case ReadMaskPixelChannel:
+            {
+              destination_image->read_mask=MagickTrue;
+              break;
+            }
+            case WriteMaskPixelChannel:
+            {
+              destination_image->write_mask=MagickTrue;
+              break;
+            }
+            case MetaPixelChannel:
+            default:
+            {
+              (void) SetPixelMetaChannels(destination_image,(size_t) (
+                destination_channel-GetPixelChannels(destination_image)+1),
+                exception);
+              break;
+            }
+          }
         channel_mask=(ChannelType) (channel_mask | ParseChannelOption(token));
         if (((channels >= 1)  || (destination_channel >= 1)) &&
             (IsGrayColorspace(destination_image->colorspace) != MagickFalse))