Image tracking device, imaging device, image tracking method, and imaging method

An imaging device, comprising:

• an imaging device that performs photometry of a photographing subject and outputs a resulting information;
• a recognition device that recognizes a photographic subject region by performing an image tracking calculation based upon image information;
• a selecting device that selects at least one focus detection area among a plurality of focus detection areas for detecting a focusing state of an optical system;
• a calculation device that performs a first calculation for detection of the focusing state of the optical system based upon a defocus amount for the focus detection area that has been selected by the selecting device;
• a control device that performs a focus adjustment of the optical system based upon output from the calculation device;
• and
• an obtaining device that obtains information of a position of the focus detection area that has been used for the focus adjustment of the optical system, wherein
• the selecting device, in a period between a first shooting and a second shooting during sequential shooting, selects the focus detection area corresponding to the position of the focus detection area, obtained by the obtaining device, that has been used for the focus adjustment of the optical system, before selecting the focus detection area corresponding to the photographic subject region which was recognized by the recognition device by performing an image tracking calculation based upon the image information, and
• the calculation device, in the period between the first shooting and the second shooting during sequential shooting, performs the first calculation for detection of the defocus amount of the optical system for the focus detection area that has been used for the focus adjustment of the optical system, before performing a second calculation for detection of the defocus amount of the optical system for the focus detection area corresponding to the photographic subject region which was recognized by the recognition device by performing an image tracking calculation based upon the image information.

An image tracking device, comprising:

• an imaging device that outputs a first image information corresponding to a first image and then outputs a second image information corresponding to a second image,
• a defocus amount calculation device that repeatedly calculates defocus amounts for a plurality of focus detection areas that are set within a photographic scene by the optical system,
• a tracking subject setting device that sets an image of a portion corresponding to a tracking subject in the first image information as a first tracking subject image,
• a tracking device that detects a second tracking subject image, corresponding to the first tracking subject image, included in the second image information, by comparing a reference information corresponding to the first tracking subject image with the second image information output by the imaging device, and
• a defocus amount determination device that determines an employed defocus amount, wherein
• if a first difference, between a first defocus amount that is the defocus amount for the focus detection area corresponding to the position of the first tracking subject image in the first image information and a second defocus amount that is the defocus amount for the focus detection area corresponding to the position of the second tracking subject image in the second information, is smaller than a first predetermined value, the defocus amount determination device determines that the second defocus amount is to be the employed defocus amount, and
• if the first difference is greater than or equal to the first predetermined value, the defocus amount determination device calculates a plurality of difference between the first defocus amount and the defocus amount for focus detection areas that are positioned peripheral to the focus detection area from which the second defocus amount were obtained, and selects one defocus amount as a third defocus amount among the defocus amounts for focus detection areas positioned at peripheral areas to the focus detection area for which the second defocus amount was detected, which has the smallest difference from the first defocus amount as a second difference, and
• if the second difference is smaller than a second predetermined value, the defocus amount determination device determines that the third defocus amount is to be the employed defocus amount.