Write proper grayscale value in bKGD chunk when writing a grayscale PNG.
diff --git a/ChangeLog b/ChangeLog
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@@ -1,5 +1,6 @@
2011-04-26 6.6.9-7 Glenn Randers-Pehrson <glennrp@image...>
- * Write the proper bKGD chunk value in grayscale PNG images.
+ * Write the proper bKGD chunk value in grayscale PNG images (reference
+ http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=18624).
2011-04-25 6.6.9-7 Anthony Thyssen <A.Thyssen@griffith...>
* Separate simple image operations from 'region' wrappers.