Processing each word:
"Many" → Lots of. "of these videos" → of these clips. "are captured using" → are recorded with. "hidden cameras" → concealed devices. "or smartphones" → "or mobile devices" or "or cell phones" "often in" → typically in "bathrooms, changing rooms, or treatment rooms" → restrooms, dressing spaces, and therapy rooms massage spy videos medical voyeur com
Breaking it down: