一种基于3维全景图像技术的深度测量方法

A Depth Measurement Approach Based on Integral Imaging

3维全景图像技术是一种能够记录和显示全真3维场景的图像技术。该技术采用微透镜阵列记录空间场景,空间任意一点的深度信息只需通过一次成像即可直接获得。本文研究采用全景图像技术直接获取物体空间信息的方法。此方法首先从全景图像中抽提视图。视图是通过抽提全景图像中对应于每个微透镜下同一局部位置的点人工合成的。每幅视图包含了全景图像中对原来的物空间场景按照某一特定方向的平行投影记录信息。接下来通过分析全景图像的光学成像过程,推导了用来描述物体深度信息和其在对应的视图间的视差关系的深度方程。从而得出空间任一点的深度可以通过其在对应视图间的视差来求得。最后,通过运用全景图像测量火柴盒的厚度的实例,验证了这一方法的可行性。其结果一方面可用于全景图像的数据处理本身,另一方面可望为开发新型的深度测量工具提供理论依据。

Integral imaging is a technique capable of displaying 3D images with continuous parallax in full natural color. Since micro-lens sheet is used in recording, only one recording is necessary in containing 3D information. The paper presents a method for extracting depth information directly from lenticular integral images. The method involves first extracting viewpoint images from the lenticular integral image. The approach starts with the constructions of special viewpoint-images from the integral image. A viewpoint-image is constructed by extracting one pixel from each micro-lens rather than a macro-block of pixels corresponding to a micro-lens unit. Each viewpoint-image contains a 2D parallel recording of the 3D scene from one particular view direction. A new mathematical expression giving the relationship between object depth and the corresponding viewpoint image pair displacement is derived by geometrically analyzing the 3D image recording process. The depth information for any object point can be calculated with its disparity between corresponding viewpoint images. The method is validated and applied to measure the thickness of a matchbox in the experiment, The results can not only be applied on the area of integral image data processing but also be expected to provide theory foundation for a novel depth extraction technique.