| 摘要 |
An apparatus and a method for detecting a VCR signal includes a horizontal tracking portion for receiving a synchronous signal of an image signal and a system clock signal, for determining and outputting a phase error between the synchronous signal and a standard horizontal synchronous signal generated by the system clock signal, and generating a horizontal synchronous signal and a vertical synchronous signal in response to the system clock signal, and a VCR signal detecting portion for receiving the vertical synchronous signal, the horizontal synchronous signal, and the phase error. The horizontal tracking portion includes a phase comparator for receiving the synchronous signal and the system clock signal, and generating the phase error, phase difference between the synchronous signal and a standard horizontal synchronous signal generated by the system clock signal, a pixel counter for receiving and counting the system clock signal, and a timing generator for receiving a pixel counter value, an output of the pixel counter, and generating a horizontal synchronous signal and a vertical synchronous signal. The VCR signal detecting portion includes a head switch pulse period generator which is reset by the vertical synchronous signal, receives the horizontal synchronous signal, and determines a specific pulse period as a head switch pulse period, and a VCR signal detector for receiving the phase error during a specific head switch pulse period, and detecting the synchronous signal as the VCR signal if the phase error exceeds a specific standard phase error value. According to the apparatus and the method for detecting a VCR signal, it is possible to more precisely detect a VCR signal.
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