1. A video signal selector comprising: a selector switch for selecting one of a first output mode and a second output mode, for outputting an endoscopic video signal as an output video signal in said first output mode, and outputting another medical video signal as said output video signal in said second output mode, said endoscopic video signal and said medical video signal being inputted in parallel with one another to said selector switch; and a selector control circuit for controlling said selector switch so as to switch from said first output mode to said second output mode in response to a first image capture command for capturing an image from said medical video signal.