Custom image filter handling multiple input images

[magick]

You found a bug. We have a patch in ImageMagick 6.2.8-6 Beta which will be available by tommorrow. A release version will be available within a week.

[magick]

6.2.8-6 is available now with the patch to fix the problem you posted.

ReplaceImageInList() should work although we normally create a new image list and append images to it and destroy the old image list:

• new_list=NewImageList();
  ...
  AppendImageToList(&new_list,image);
  ...
  DestroyImageList(images);
  *images=new_list;