PURPOSE:To realize a reproducing system without flickering of color by using a video signal processing circuit provided with a non-input state detecting circuit detecting that no video signal is inputted as a video signal detection circuit. CONSTITUTION:When a prescribed level is given to an input terminal 1 while no signal is inputted, an output of a synchronizing signal separating circuit 2 is a constant level, and the 2nd counter 6 and a detection circuit 19 output always an H level independently of the circuit operation. A gate circuit and a NAND element 14 of a reset pulse generator 5 do not output a reset pulse, and when the 1st counter 4 keeps counting of reference clocks for 4H periods, the detection circuit 17 outputs and L level signal, an output of a NAND element 23 of a non-input state detection circuit 7 goes to an H level and is outputted from an output terminal 8. When the state transfers from the non- input state to the state of video signal input, an L level is outputted from a detection circuit 22 after 3H and the output of the NAND element 23 goes to L level.