The camera company claims that three separate individuals review the video of the incident to determine if a violation has been committed. In addition, a sworn police officer (the one who signed your ticket) also reviews the incident. If you did come to a complete stop before the line, the ticket should never have been issued. If you came to a complete stop, but it was after the line, well, technically you have violated the law, as you are prohibited from entering an intersection against a red light. If you did come to a complete stop after the line, most of the time the ticket will not be issued. Most of the time, but not always.
The fact there is no sign that says no right turn on red doesn’t matter. The only issue on these photo enforcement systems is whether you entered the intersection when the light was red without coming to a complete stop.