Patent ID: 7212246

Claim:
An image signal format detection apparatus, comprising: a first summed absolute difference (SAD) value calculation unit to calculate, from a previous field, a current field, and a next field of an image signal with time-consecutive fields, a first SAD value with reference to pixel values of the current field and the previous field; a second SAD value calculation unit to calculate a second SAD value with reference to pixel values of the current field and the next field; a pattern generation unit to generate a detection pattern based on a result of a comparison of the first and the second SAD values; and a pattern analysis unit to store the detection pattern, compare the stored detection pattern of with a predetermined verification pattern, and determine whether the image signal is an image signal generated by a 2:2 pull-down, wherein the pattern generation unit comprises: a SAD comparator to compare magnitudes of the first and the second SAD values; and a multiplexer to selectively output either a corresponding first value or second value based on a result of the comparison of the SAD comparator.