CRT monitor image identification manner and CRT monitor image identification unit

摘要

PURPOSE:To display a normal image signal onto an area of a CRT monitor without designation of area on each occasion by discriminating the display area of a CRT for an output signal of a video camera and filling the area in a specific color and synthesizing the signal to be displayed on the CRT monitor at the region. CONSTITUTION:An image of an object including a CRT image is given to video cameras A, B by a half mirror in an optical system 1 and control signals S1, S2 are used to control shutters so that one shutter is open while the other is closed. Two obtained image pickup signals are given to a difference absolute value calculation section, in which a difference is obtained for each picture element and a discrimination section 6 discriminates a picture element of a difference absolute value larger than a prescribed threshold level to be a CRT monitor display area and fills in the area in a specific color. A signal is displayed on the CRT monitor section to e displayed normally by synthesizing CRT monitor signals in this area and even when an object is in existence between the CRT monitor and the video camera, a CRT monitor signal is normally displayed.