Patent ID: 7962663

Claim:
A signal input system to input an image signal from source equipment to sink equipment through a High Definition Multimedia Interface, wherein: the source equipment comprises a transmission section to transmit a format signal to the sink equipment through a predetermined first line in the High Definition Multimedia Interface, the format signal having a voltage value corresponding to a format of the image signal; the sink equipment comprises: a reception section to receive the format signal transmitted through the first line by the transmission section; a judging section to judge the format of the image signal based on the voltage value of the format signal which is received by the reception section; and a setting section to set an image output based on a judgment result of the judging section; and wherein the first line is a line to perform a transmission and a reception of a hot plug signal which indicates that the source equipment and the sink equipment are connected to each other; and the format signal has a function as the hot plug signal.