The field correlation detection circuit and the cinema signal detection circuit null 1 field delay

摘要

PPROBLEM TO BE SOLVED: To provide a field correlation detecting circuit, in which only one field delay device for detecting 24 frames or 30 frames per second is required and used in common, and a cinema signal detecting circuit by using the field correlation detecting circuit. PSOLUTION: In a comparator 14, an absolute value of difference between an input field signal and a field signal of one field ahead field, which is outputted from a one-field memory 11, is compared with a threshold value R1. In a pixel counter 15, the number of '1', which is outputted when the absolute value is larger than the threshold value R1, is counted for one field, and a difference between the counted value and the counted value in the one field ahead field is detected by a difference detector 17 to obtain a field correlation signal. PCOPYRIGHT: (C)2004,JPO&NCIPI