***** NOT A TEACHER *****
Hello, Mehrgan:
Maybe you are looking for the verb "to pixilate." (My dictionary gives two other spellings.)
Just the other morning, I turned on my TV and saw a report of a pilot who had been shot down over ____. They showed his face, but the picture had been pixilated below the waist. I can only guess that in being shot down, the pilot had lost part of his clothing, or maybe his captors had stripped him.
James