PURPOSE: To reduce the cost and dot disturbance by eliminating a chrominance signal component through a low pass filter after a vertical profile signal component is separated from a digital composite color video signal converted into a sequential scanning system by using a comb line filter.

CONSTITUTION: The vertical profile signal 508 is formed by four THS delay circuits 126 and a vertical profile circuit 501. The vertical frequency characteristics of a vertical HPF601 used in this case is fixed in the horizontal frequency direction and changing only in the vertical frequency direction, and this change is; gain=0 at F=0 and then the gain is increased and gain=1 at F=0.5×fHS/fv. Since a C signal component is included in an output signal 609 of the vertical HPF601, the signal is inputted to an LPF608 of the next stage in order to eliminate the C signal component. The LPF607 consists of 2Tck delay circuits 610∼ 613, coefficient multipliers 614∼618 and an adder circuit 619 and has the low pass filter characteristics having a band of nearly 2MHz. The C signal included in the signal 609 is eliminated almost completely including its high frequency components by the characteristics above.