I tried to 3 methods, only one works well (without too much trouble) with Cygwin:
1. install the binary windows version directly ( ftp://ftp.imagemagick.org/pub/ImageMagick/binaries/). This works in Windows, but not in the cygwin flavor: the display.exe does not work under mintty or other bash shells. Even after I setup export DISPLAY=localhost:0.0, it still complains about: “display.exe: unable to open X server `(null)’ @ display.”
2. build from source code using the ImageMagick’s package (ftp://ftp.imagemagick.org/pub/ImageMagick/), but it seemed that there are some packages, such as QLR, are missing. And after configuration the “make” step failed.
3. searched if cygwin contains a ImageMagick package from the online cygwin package list (http://www.cygwin.com/packages/), it turn out to be in the “graphics” category. After installing it, display.exe was still not working. Then I started the X-Server, and included
into ~/.bashrc. Then it works.