Digital camera and method of controlling same

Abstract

Whether a portrait photography mode has been set is determined. A first threshold value is set when the portrait photography mode has been set and a second threshold value that is smaller than the first threshold value is set when the portrait photography mode has not been set. A cross-correlation coefficient between the image of the subject and a template image is calculated. The calculated coefficient and the set threshold value are compared and the position of the image of a face is detected in the image of the subject. When the portrait photography mode has been set, it can be construed that the subject contains a person and therefore the position of the face image can be detected comparatively accurately by increasing the threshold value.

Description

[0001]The present Application is a Divisional Application of U.S. patent application Ser. No. 10 / 841,510, filed on May 10, 2004.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]This invention relates to a digital camera (inclusive of a digital still camera, digital movie camera and a portable information device having a camera function) and to a method of controlling the operation thereof.[0004]2. Description of the Related Art[0005]In a case where a picture of a person is taken using a digital camera, often the camera is focused on the face of the person. Focusing is easy if the face is at the center of the shooting zone but the face is not always at the center of the shooting zone. There are occasions, therefore, when it is necessary to detect the image of the face in the image of the subject. For example, there is a technique that involves extracting the portion of the subject image that corresponds to the color of the face from the image, extracting the edge of th...

AI Technical Summary

Benefits of technology

The system achieves precise face detection and prevents unnatural images by adjusting threshold values and issuing alarms when a face is not present in portrait mode, while halting unnecessary processing in non-portrait modes, resulting in more accurate and efficient image capture.

Problems solved by technology

A problem with this technique, however, is that the precision of the processing for extracting the image of the face is not always high.

If the portrait photography mode has been set regardless of the fact that a person does not exist in the subject of photography, an unnatural image may be obtained.

Furthermore, in a digital camera that can be set to a scenery photography mode, it is wasteful to try and detect the image of a face if the scenery photography mode has been set.

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