基于景物散焦图像的距离测量

计算机视觉中，景物三维重建的关键是从景物的图像中计算出景物目标到摄像机的距离，提出了一种基于散焦图像计算景物距离的新方法。该方法利用远心光学镜头拍摄景物图像，通过改变像检测到镜头的距离获得同一景物的两幅散焦程度不同的图像，将获得灰度图像转换成梯度图像。利用矩不变原理计算梯度图像中边缘区的大小与整个图像匹配大小的比Pe,根据两幅图像的Pe值计算出景物的深度。实验结果表明了该方法的有效性，并对该方法产生的误差进行了分析。

DEPTH MEASUREMENT BASED ON DEFOCUS IMAGE

In computer vision, the key of 3 D reconstructing is to figure out the depth information of a scene from its images. A new method for depth from defocus images is proposed. Two images of the same scene are taken with different defocus by changing the distance between lens and image plane using telecenter lens. The observed two defocus gray level images are converted into gradient image. The ratio P e between the edge region and the entire gradient image is calculated using moment preserving principle. According to P e of two images, the depth of scenery is determined. Experiments results show that this method is effective. The error of this method is analyzed.