2 NH3 + 4 O2 --> 2 NO + 3 H2O
2 NO + O2 --> NO2
2 NO2 + 1/2 O2 + H2O --> 2 HNO3(aq)
... way, they were able to impose whatever restrictions they chose on the playback of such movies. See also DIVX for a more draconian and less commercially successful ...