Don't generalize your own habits to everybody in here.
plus if you don't have any idea about a subject just stay quiet.

camera flashes when you pass over the sensors which are installed just on pedestrian walkway in front of you. its not necessary to cross the whole signal to get flashed.

my case was exactly the same, happened in small signal near apollo polyclinic. i went over the pedestrian walkway by the same mistake and then returned. i believe he didn't cross the signal coz the opposite side traffic was flowing.

camera takes two snapshots plus a short video. even if they fine, he can appeal and video is his proof.