METHOD FOR ADJUSTING PHOTOGRAPHING SETTINGS OF DIGITAL CAMERA THROUGH MOTION DETECTION

• US 20110019013A1
• Filed: 07/15/2010
• Published: 01/27/2011
• Est. Priority Date: 07/22/2009
• Status: Active Grant

• Current Assignee: Altek Corporation
• Original Assignee: Altek Corporation
• Inventors: Chou, Hong-Long, Tseng, Chia-Chun, Lin, Horng-Horng
• Granted Patent: US 8,159,544 B2
• Time in Patent Office: Days
• US Class Current: 348/208.4
• CPC Class Codes: H04N 23/611 where the recognised objects include parts of the human body
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 5/144 Movement detection for video coding H04N19/503; analysis of motion in general G06T7/20

Abstract

A method for adjusting photographing settings of a digital camera through motion detection, for determine to adjust the photographing settings of the digital camera according to vibrations of the digital camera or shaking of a photographed object. The adjusting method includes the following steps. At least two continuous pre-photographed images are captured. A central area and an edge area are set at same positions in the pre-photographed images respectively. Feature points are found in the pre-photographed images. A local motion vector and a camera motion vector are respectively determined according to a relation of the feature points on the central area and the edge area. A subject motion vector is generated according to a difference between the local motion vector and the camera motion vector. Adjustment of the photographing settings of the digital camera is determined according to a maximum value in the subject motion vector and camera motion vector.

Claims

1. A method for adjusting photographing settings of a digital camera through motion detection, applied in a digital camera for photographing a digital image, so as to determine to adjust the photographing settings of the digital camera according to shakes of the digital camera or a photographed object, comprising:

capturing two continuous pre-photographed images, and defining the two images as a first pre-photographed image and a second pre-photographed image;

setting a central area at the same position on the first pre-photographed image and the second pre-photographed image respectively, wherein the central area further comprises a plurality of first image blocks;

setting an edge area at the same position on the first pre-photographed image and the second pre-photographed image respectively, wherein the edge area further comprise a plurality of second image blocks, and the central area and the edge area do not superpose each other;

finding a plurality of feature points according to the first image blocks and the second image blocks;

establishing a corresponding local motion vector from the first pre-photographed image and the second pre-photographed image according to each of the feature points;

establishing a camera motion vector by performing a similarity calculation program on the local motion vectors selected in the edge area;

generating a subject motion vector according to a difference between the local motion vector and the camera motion vector; and

adjusting photosensitivity when the digital image is photographed according to a maximum value in the subject motion vector and the camera motion vector.

2. The method for adjusting photographing settings of a digital camera through motion detection according to claim 1, wherein the step of finding the feature points further comprises:

calculating an absolute error of brightness of each pixel in the first image blocks in the first pre-photographed image and the second pre-photographed image;

calculating an absolute error of brightness of each pixel in the second image blocks in the first pre-photographed image and the second pre-photographed image;

selecting a plurality of selection blocks from the first image blocks and the second image blocks according to the absolute errors of the image blocks; and

filtering all pixels in each of the selection blocks respectively, selecting a pixel satisfying a high-frequency threshold value from the filtered pixels, and defining the selected pixel as the feature point.

3. The method for adjusting photographing settings of a digital camera through motion detection according to claim 2, wherein the filter is a Sobel filter or a sharpness filter.

4. The method for adjusting photographing settings of a digital camera through motion detection according to claim 1, wherein an aperture value when the digital image is photographed is further adjusted according to a difference value between the subject motion vector and the camera motion vector.