The one on the left (in the hat) is writer/director Michael Schlesinger, making what he calls his "Hitchcock cameo a la 'Dial "M" For Murder.'" The one on the right is veteran character actor Dick Miller; the two are friends, but Schlesinger didn't want to impose upon him for just a bit part, so he came up with the gag of using his photo. (Dick and his wife Lainie are both thanked in the end credits.) Incidentally, Miller has frequently worked with Robert Picardo, who's looking at the pictures in the scene, hence his puzzled glance at the camera.