Electronic unit controlled by a photographing system including a pattern detection system

摘要

A photographing system includes: a photographing section photographing a subject to acquire a frame image including a subject image; and a matching section repeats image search through pattern matching between a template image and a subject image while sequentially changing a size ratio of the template image to the subject image, and obtains one or more size ratios at which patterns match each other, in a certain order of image search, and holds a size ratio having a largest value among such obtained size ratios as a first size ratio, and thereafter performs image search in a manner that pattern matching is performed at a first frequency in a range of a size ratio equal to or larger than the first size ratio, and is performed at a frequency lower than the first frequency in a range of a size ratio smaller than the first size ratio.

<Paragraphs id="pa02" num="0002" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">The photographing system may be used to control the backlight of a display, e.g. to switch on when a viewer or viewers is / are detected in the frame image.