Patent ID: 7489364

Claim:
A Y/C separation circuit, comprising: a band selecting section outputting a first video signal, a second video signal, and a third video signal by means of extracting signals which include a chrominance subcarrier from three composite video signals that are delayed from one another by one or two horizontal scanning periods; a pattern determination section determining relations in amplitude and phase between the first video signal, the second video signal, and the third video signal; and a filtering section executing an operation for separating a chrominance signal based on the determination result of the pattern determination section to output the chrominance signal, wherein the pattern determination section determines the relations in amplitude and phase between the first video signal, the second video signal, and the third video signal by positive/negative determination which determines whether the first video signal, the second video signal, the third video signal, an addition signal obtained by adding two of the video signals, and a subtraction signal obtained by subtracting two of the video signals take positive values or negative values.