Stereo viewing zone in parallax-barrier-based autostereoscopic display

A well-designed parallax barrier autostereoscopic display can produce high-quality stereo images with little crosstalk or even without crosstalk in the stereo viewing zones. The concept of stereo image quality factor was defined to indicate the stereo viewing zone of an autostereoscopic display. According to the structure and principle of the display, the formulae of stereo image quality factor were deduced. Simulated program was developed to calculate stereo image quality factor. The simulated results of stereo image quality factor for a 19-in autostereoscopic display monitor show that stereo image quality factor can indicate the stereo viewing zone of autostereoscopic displays. The simulated results also show that the value of stereo image quality factor is equal to 1 at only few positions where viewers can see very good stereo images without crosstalk. And the viewers who stay at the optimal viewing distance can see the best stereo images on the display screen. The research of the stereo viewing zone helps in the design of such autostereoscopic display devices with little or without crosstalk.     

立体图像质量的主观评价方案

立体图像质量评价在立体图像压缩、处理以及通信领域中有着十分重要的作用,一种好的立体图像质量客观评价方法也要依赖于立体图像的主观评价.本文基于人眼的立体视觉特性,提出了相对完整的立体图像质量主观评价方案,该方案主要分为立体图像库的建立、评测者的选择、观看条件的描述、评测者的训练和测试、数据处理和实验结果分析六个方面.实验中,评测者根据自己的主观感受,对所选取的立体图像进行评分,最后用数理统计理论对所得数据进行处理.结果表明,本文所提出的主观评价方案可行,能够正确反映立体图像质量的优劣.     

立体图像质量的主观评价方案

立体图像质量评价在立体图像压缩、处理以及通信领域中有着十分重要的作用,一种好的立体图像质量客观评价方法也要依赖于立体图像的主观评价.本文基于人眼的立体视觉特性,提出了相对完整的立体图像质量主观评价方案,该方案主要分为立体图像库的建立、评测者的选择、观看条件的描述、评测者的训练和测试、数据处理和实验结果分析六个方面.实验中,评测者根据自己的主观感受,对所选取的立体图像进行评分,最后用数理统计理论对所得数据进行处理.结果表明,本文所提出的主观评价方案可行,能够正确反映立体图像质量的优劣.     

Implementation of opto-digital stereo object tracking system

In this paper, a new opto-digital stereo object tracking system using the variable window mask and the optical binary phase extraction joint transform correlator (BPEJTC) is proposed. At the first step, with the distance information from the stereo camera to the tracking object easily acquired by the structural elements of a stereo vision system, the area of the tracking object can be digitally extracted by using the variable window mask. And, at the second step, by carrying out the optical BPEJTC between this reference image obtained from the variable window mask and the stereo input image, the coordinates of the tracking object's location can be acquired, and then with these values, the convergence angle and the pan/tilt of the stereo tracking camera can be finally controlled. From some experimental results, the proposed system is found to be able to effectively extract the area of the target object from the input image having the background noises by using the variable window mask. And, with the location values of the tracking object obtained by using the optical BPEJTC, the convergence angle and the pan/tilt of the stereo cameras can be controlled. Finally, a feasibility of real-time implementation of the adaptive stereo object tracking system using the proposed algorithm is also suggested.     

狭缝光栅自由立体显示器立体可视区域的研究

提出了反映观察区域某一点是否是合适的立体观察点立体图像质量因子的概念.根据狭缝光栅自由立体显示器的结构和工作原理并应用几何光学知识,分析得出了立体图像质量因子的计算公式,并给出了立体显示器的立体图像质量因子的计算结果.通过定义立体图像质量因子的阈值,得到狭缝光栅自由立体显示器的立体可视区域.     

TDI CCD立体相机内方位元素测试技术研究

依据星载单镜头TDICCD立体相机立体成像及测绘要求,结合普通测绘相机内方位元素,提出了星载单镜头立体相机内方位元素由焦距、主点位置、立体成像角(前后视交角)、图像畸变等元素组成。给出了立体相机内方位元素测试的方法,针对立体相机成像特点给出了计算内方位元素的算法,对其进行了实际测量和验证,其测量结果符合设计要求。     

一种基于柱透镜光栅的计算机辅助彩色立体图片合成方法

对基于柱透镜光栅的立体照片的制作原理进行了理论分析,推导了立体成像的光学原理,结合现代数字图像处理技术,对多幅图像的匹配及合成方法进行了分析,提出和实现了一种计算机辅助彩色立体图片合成方法。实验结果表明,利用计算机系统进行彩色立体图片制作是一种完全可行的方案,较之传统的立体照片制作工艺,在经济性及使用灵活性等方面具有非常明显的优势     

Three-dimensional imaging and visualization of partially occluded objects using axially distributed stereo image sensing

In this Letter, we propose a multiperspective three-dimensional (3D) imaging system using axially distributed stereo image sensing. In this proposed method, the stereo camera is translated along its optical axis and multiple axial elemental image pairs for a 3D scene are collected. The captured elemental images are reconstructed in 3D using a computational reconstruction algorithm based on ray back-projection. The proposed method is applied to partially occluded object visualization. Optical experiments are performed to verify the approach.     

一种用于时空立体视觉的光源模式设计

时空立体视觉是一种全新的三维重建技术,它利用主动光源来改变图像灰度,通过比较某时间段内的图像序列来完成立体匹配。针对时空立体视觉的特点,设计了一种由多级对偶的和沿一维单调变化的"锯齿式"灰度条纹组成的光源,提高了鲁棒性。三维重建实验结果说明了该光源的有效性。     

单目多视点立体图像提取及应用

设计并实现了一种基于广角相机和平面镜的单目多视点立体图像摄像系统,给出了硬件装置的设计指标和优化方法;同时,在研究了硬件系统的标定方法基础上,实现了其在三维测距方面的应用。多枚平面镜构成的对称斗型腔体被放置在广角相机前面,物体光线经过不同平面镜反射后,投影到相机图像平面的不同区域,在相机投影平面上生成物体多个影像,形成单目多视点投影图像。该类图像等价于视点不同的多幅图像,可以使用多视点立体视觉算法实现三维测量。     

立体声技术近年来的进展

本文总结和评论了立体声技术近年来的进展，包括声像定位理论和实验，传统的双通路立体声系统的改进，环绕产系统，高清晰度电视声系统，假头型立体声系统，数字声频技术在立体声的应用等．文中最后还叙述了对立体声今后发展的展望．     

Stereoscopic video surveillance system for detection of target’s 3D location coordinates and moving trajectories

In this paper, a novel stereoscopic video surveillance system to track a target person and detect its three-dimensional (3D) location coordinates and moving trajectory is implemented by using the pan/tilt-controlled stereo camera system. Stereoscopic video images of a target person are captured with stereo camera system and the target face and its location in the left image plane can be detected by use of YCbCr color model and centroid method. Also the target location in the right image plane can be obtained through correlation between the left face image and the right image by using the binary phase extraction joint transform correlator (BPEJTC) algorithm. With these location data of the target face in the left and right image planes the pan/tilt systems can control the stereo camera to track a target person by positioning the target face at the center of the camera’s FOV and making the focusing points of the right and left camera coincided on the target face. And then, with the resultant pan/tilt angles and geometric parameters of the stereo camera system, the target’s real 3D location coordinates and moving trajectory in the world space can be obtained. From some experiments with 900 frames of stereoscopic video image pairs, it is analyzed that the target’s center location after being tracked is kept to be very low error ratio of 0.62%, 2.04% on the average in the x, y directions of the image plane, respectively. Also, the error ratio between the calculated and measured values of the 3D location coordinates of a target person is found to be very low value of 2.1%, 5.7% on the average in the X and Y directions of the real world space, respectively.     

基于深度约束的水下稠密立体匹配

针对双目水下图像匹配不满足空气中常规极线约束的问题,提出一种基于深度约束的半全局算法以实现水下稠密立体匹配.首先采用深度约束确定匹配过程的深度约束搜索区域.然后,基于深度约束区域将绝对差值和梯度计算推广到二维区域并进行加权融合.在深度约束区域内的搜索过程中,采用胜者为王的策略确定某一视差值下的最佳行差及最佳行差下的匹配代价,并将其作为能量函数的数据项应用于半全局算法中,进行匹配代价的聚合.最后采用抛物线拟合法得到亚像素级的稠密视差图.在水下图片上进行的稠密立体匹配结果表明:相较于其他半全局匹配算法,本文算法在极大提高运行速度的前提下,可以获得良好的水下稠密立体匹配效果.     

Anaglyph stereo visualization by the use of a single image and depth information

In this paper, an anaglyph stereo visualization is studied by the use of a single image and depth information. The present technique allows the stereo visualization of the target image without binocular camera, which has been used for generating the standard anaglyphs. Three test cases are shown in this work, which covers the generation of monochrome anaglyph from given geometrical information, and that of monochrome and color anaglyph from depth information evaluated from other imaging devises, which are placed in parallel. The experimental depth information of the target image is evaluated from the correlation-based template matching analysis of the random dot patterns optically projected on the target objects. Examples of anaglyph stereo visualization are shown for scientific art, such as the monochrome cube, monochrome plaster figure and the color artificial flowers. These results indicate that the present technique of anaglyph stereo visualization through the depth information is very useful and widely applicable to the general three-dimensional visualization.     

光电混合变换相关器在体视测距中的应用

本文研究了体视测距系统的图像联合变换相关原理，推导出利用像联合变换相关测量目标距离的公式。同时，本文表明把光电混合联合变换相关器用于体视测距系统的原理装置和测距实验。     

Single-camera panoramic stereo system model based on skew ray tracing

This study integrates panoramic imaging and stereo vision theory to propose an innovative 3D optical positioning method for single-camera panoramic stereo imaging systems. The conventional single-viewpoint theory based on pinhole modeling is replaced by a skew ray tracing methodology to establish the geometrical relationships of object and image. An analytical model of a single-CCD panoramic stereo imaging system is then established by adopting a catadioptric imaging system, a single-CCD stereo panoramic vision system and the presented skew ray camera calibration method.     

A robust method for the reconstruction of disparity maps based on multilevel processing of stereo color image pairs

A novel method for the reconstruction of disparity maps (DMs) with robust properties to nonideal registration conditions, reflections, and noise in stereo color image pairs has been substantiated for the first time. The novel approach proposes a scheme for image DM reconstruction where Jaccard distance metric is used as a proximity criterion in stereo image pair matching. A physical interpretation of the method that allows the quality of the formed DMs to be improved significantly is given. A processing block diagram has been developed in accordance with the novel approach. Simulations of the novel DM reconstruction method have shown an advantage of the proposed DM reconstruction scheme in terms of generally recognized criteria, such as the structural similarity index measure and the bad matching pixels, and when visually comparing the formed DMs.     

单线阵CCD相机定位精度评估模型及几何误差研究

为满足单线阵CCD相机立体测绘定位的需求,研究了相机几何误差对定位精度的影响,并建立了它们之间的数值模型,为相机的几何指标分析和量化提供理论支持.首先针对单线阵立体成像特点,分析了几何标定和像点量测误差对定位结果的影响;然后以前方空间交会公式为基础,推导出定位精度评估模型.该模型给出了定位精度随几何标定和像点量测误差的...     

计算机辅助彩色立体图像生成中的误差分析与处理

柱透镜光栅的计算机辅助立体成像的基本原理是将二维序列图像进行切分和重组,使之以三维模型的形式展现,使合成的图像在柱透镜光栅下观察时具有"纵深感"。该项技术在广告、摄影、电影制作中具有广泛的应用。但是长期以来,在图像切分时并不能保证像素一定被整除,这意味着剩余像素的出现,合成的立体图像必然存在误差。如何处理剩余像素的问题一直是个难题,阻碍了该技术的推广。针对立体图像生成方法中的剩余像素问题,详尽地分析了误差的形成,并提出了强行取整算法和误差分散算法两种误差处理方法。实验表明,这两种算法能较好的处理剩余像素,增强了合成图像的立体效果,这将有助于立体成像技术的进一步推广。     

An infrared salient object stereo matching algorithm based on epipolar rectification

Due to the higher noise and less details in infrared images, general matching algorithms are prone to obtaining unsatisfying results. Combining the idea of salient object, we propose a novel infrared stereo matching algorithm which applies to unconstrained stereo rigs. Firstly, we present an epipolar rectification method introducing particle swarm optimization and K-nearest neighbor to deal with the problem of epipolar constraint. Then we make use of transition region to extract salient object in the rectified infrared image pairs. Finally, disparity map is generated by matching salient regions. Experiments show that our algorithm deals with the infrared stereo matching of unconstrained stereo rigs with better accuracy and higher speed.