Patent ID: 7916216

Claim:
A video signal converting device for converting an analog composite signal into a digital signal, comprising: a sampling clock output unit to output a sampling clock signal having a frequency which is 4n times the frequency of a burst signal contained in said analog composite signal (n represents a positive integer of 2 or greater); an analog-to-digital converter to convert said analog composite signal into a digital signal based on said sampling clock signal; and a digital signal extracting unit to extract every n digital values from a predetermined sampling phase of digital values output from said analog-to-digital converter, and output the extracted digital values; wherein said digital signal extracting unit comprises: a negative-going-edge detecting unit to detect a negative-going edge of a horizontal synchronizing signal of said analog composite signal; a comparing unit to compare the digital values on the negative-going edge of the horizontal synchronizing signal with a sampling phase determining value; and a sampling phase determining unit to determine said sampling phase based on the result of the comparison from said comparing unit.