| 摘要 |
When a continuous wave signal synchronized with a first color subcarrier signal is generated (color subcarrier extracting circuit 2, phase error detecting circuit 3, A/D converting circuit 4, digital oscillating circuit 5) from an analog video signal containing a first color subcarrier signal supplied to an input terminal 1 and a digital video signal containing a color signal component supplied to an input terminal 7 is converted (digital video signal converting circuit 6) into a composite video signal containing a carrier chrominance signal, a color signal component is converted into a carrier chrominance signal by using the continuous wave signal and a phase of a first color subcarrier signal contained in the analog video signal and a phase of a second color subcarrier signal of a composite video signal formed from the digital video signal are synchronized with each other. According to this arrangement, a phase of the carrier chrominance signal of the analog video signal and a phase of a carrier chrominance signal contained in the composite video signal formed from the digital video signal can be synchronized with each other by the simple arrangement, for example, and hence an image expressed by the digital video signal and an image expressed by the analog video signal can be easily synthesized with each other. <IMAGE> |
