Image detection device, focusing device, image-capturing device, image detection method, and focusing method

Abstract

An image detection device includes: a subject detector that acquires image information in an image field of an imaging optics with an image sensor, and detects a position of a subject in the image field based upon reference information related to an image of the subject and the image information; and a magnification detector that detects a magnification of the imaging optics. And the subject detector starts operation to detect the position of the subject, when the magnification has become greater than or equal to a predetermined value.

Description

INCORPORATION BY REFERENCE[0001]The disclosures of the following priority application and U.S. patent document are herein incorporated by reference: Japanese Patent Application No. 2007-179210 filed Jul. 9, 2007; and U.S. Pat. No. 5,659,816.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to an image detection device, a focusing device, an image-capturing device, an image detection method, and a focusing method.[0004]2. Description of Related Art[0005]An auto focus system is per se known that is endowed with an automatic focus (AF) function of detecting the defocus amounts of a photographic lens for a plurality of focus detection areas that are set within the photographic scene, and driving the focus lens to focus it based upon the defocus amount of any one of those areas, and with an image tracking function of storing an image of a photographic subject in the photographic image that is to be the subject of tracking as a template image (a...

AI Technical Summary

Benefits of technology

The present invention relates to an image detection device and method that can accurately detect the position of a subject in a photographic image. The device includes a subject detector, a magnification detector, and a focus detector to detect the position of the subject. The device can also detect the position of the subject based on a reference image and the position of the subject in the image. The invention can improve image tracking and prevent confusion when multiple subjects or background objects are present in the image. The device can also include a judging circuit to determine the reliability of the focus detection. Overall, the invention improves the accuracy and efficiency of image detection and tracking.

Problems solved by technology

When performing image tracking using this type of template image, the possibility is high that some photographic subject other than the proper tracking subject, or a portion of the background, will mistakenly be taken as being the tracking subject, and in this case the problem arises that the tracking performance of the image tracking function deteriorates.

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