Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
That reads in the image, then it makes a clone of it inside the parentheses. It scales that clone down to 10% then back up to its original dimensions which pixelates the entire clone. Then it crops the area you want, and using "-coalesce" it places that cropped area in its original location on a transparent background. It finishes outside the parentheses by compositing the pixelated area on the original input image and writes the output.
Resizing a region works fine for some versions of IM, such as v6.9.9-50. But it doesn't work in v7.0.7-28.
Initially, "-region" wasn't available in v7. Then I think "-region" code was re-written for v7, and I guess the new v7 code doesn't do what the old v6 code did.
I tried installing v6 and with the original command doesn't exactly work ok with the koala image, but it works.
Using the below command it works just fine pixelating faces: