To obtain a low-cost video signal processing apparatus by removing a comparator and a predetermined value generating circuit which are doubly present in the apparatus.
A comparator 10 compares a signal obtained by FM-demodulating a color identification signal with a predetermined value generated in a predetermined value generating circuit 11. The result of comparison is delayed by 1H period by a 1H sample hold circuit 12 to generate a line ID signal. This line ID signal and a signal obtained by delaying this signal by 1H period by the sample hold circuit 32 are inputted into an exclusive disjunction circuit 30, and the exclusive disjunction output is used as a SECAM determining signal. Thus, the necessity of the predetermined value generating circuit and the comparator which are required for determination of a SECAM system signal is eliminated.
FUJII KUNIHIKO
MIYOSHI TOSHIHIRO
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