In the single player game, press the pause button and select Option

Select the extra CHEAT option, ENABLE is open, DISABLE is closed. Effect at a glance 2 computers: CODNoir changes the game screen to black and white. 4 computers: Photo-Negative in-game screen inverse color, black to white, white to black, and so on 6 computers: SuperContrast contrast increase, can be mixed with the first two effects 8 computers