Digital picture and auxiliary data transmission system for use in plant

A transmission system to transmit a digital picture taken from a TV camera and auxiliary data superimposed on the 525th horizontal line of the NTSC picture signal is constructed. The 525th horizontal line is used to transmit auxiliary data, i.e., temperature data, humidity data, and vibration frequency data, in place of picture codes. The 525th horizontal line is effectively used as an auxiliary data line since the 525th horizontal line is masked behind the retrace period of the picture signal on a visual display. The basic system can transmit auxiliary data 30 times per second on the 525th horizontal line. The rate of transmitting auxiliary data was up to 196.8 kbits per second. Picture signals and auxiliary data were satisfactorily transmitted at the same time. Using semiconductor memories, continuous data was transmitted together with NTSC digital pictures.