Patent ID: 8542292

Claim:
A flicker correction device for reducing 60 Hz flicker of an image captured at a field frequency of an NTSC system using an imaging element in which the exposure time for each line begins sequentially or an imaging element in which the exposure time for each point begins sequentially, the flicker correction device comprising: a line average value calculation section which calculates an average value for each line during the validity period of an input image signal; a storage section which stores, in the unit of one frame period, the average values obtained by the line average value calculation section; a movement detection section which detects movement from an output change between the average value obtained by the line average value calculation section, and the one-field preceding field average value stored in the storage section; a difference value calculation section which calculates a difference value between the average value obtained by the line average value calculation section, and the n-field preceding field (n: an integer multiple of 3) average value obtained in the storage section; a division value calculation section which calculates a division value by dividing the average value obtained by the line average value calculation section, by the difference value obtained by the difference value calculation section; a flicker component extraction section which extracts a flicker frequency from the result of the division value calculation section; a flicker determination section which determines whether flicker exists or not, and whether the flicker frequency is 60 Hz or not, from the results of the flicker component extraction section and of the movement detection section; a flicker correction gain calculation section which calculates a flicker correction gain synchronized with the flicker frequency from the result of the flicker determination section; and a flicker correction gain multiplication section which multiplies the image signal by the correction gain obtained by the flicker correction gain calculation section.