1. An electronic camera having a function to determine and display an object area in respective frames of images sequentially captured, the object area including an image of an object to be tracked, said electronic camera comprising: a tracking processing unit configured to search a predetermined range in a frame included in the respective frames, using a first feature amount previously registered and quantitatively indicating a feature of the object, to calculate a first evaluation value indicating a degree of matching between an image in an area obtained as a result of the search and the image of the object, and to determine a target area estimated to include the image of the object, based on the first evaluation value calculated; an update area calculation unit configured to search the predetermined range in the frame, using a second feature amount that is different from the first feature amount and quantitatively indicates a feature of the object, to calculate a second evaluation value indicating a degree of matching between an image in an area obtained as a result of the search and the image of the object, and to determine, within the frame, an update area for updating the first feature amount, based on the second evaluation value calculated; an update determination unit configured to determine whether or not to update the first feature amount by checking whether or not at least one of the first evaluation value and the second evaluation value satisfies a predetermined condition, the first evaluation value being calculated by said tracking processing unit, and the second evaluation value being calculated by said update area calculation unit; a registered feature amount updating unit configured to update the first feature amount with another first feature amount extracted from the update area, when said update determination unit determines to update the first feature amount; and a tracking result drawing unit configured to determine, as the object area, the target area determined by said tracking processing unit and draw information on the target area when said update determination unit determines not to update the first feature amount, and to determine, as the object area, the update area determined by said update area calculation unit and draw information on the update area when said update determination unit determines to update the first feature amount, wherein when the first feature amount that is previously registered is updated, said tracking processing unit is configured to determine another target area within another frame, using the updated first feature amount.