International Space Station
The color of the callsign in the upper left of the image indicates which of the 4 cameras took the photo.
Red callsign [-Y pointing camera, mirror reverses image].
Green callsign is the top view [+Z pointing camera] and sometimes has the 2 meter antenna in view.
Blue callsign is the bottom view [-Z pointing camera].
Magenta callsign [+Y pointing camera, mirror reverses image].