多通道大屏幕图像无缝拼接技术研究

发布时间：2018-06-11 12:32

本文选题：大屏幕显示 + 多通道　；参考：《北京交通大学》2011年硕士论文

【摘要】：近几年来,随着投影显示技术的不断发展,大屏幕拼接技术已广泛应用于虚拟仿真培训、指挥控制、工业制造设计、科学研究和复杂决策等过程,并在广告、展览展示、娱乐领域的应用越来越流行。目前广泛使用的大屏幕显示系统,采用的是高性能的投影仪,其成本十分昂贵,难以普及。研究采用基于摄像机的多个投影仪拼接高分辨率大屏幕显示系统具有一定的实用价值和现实意义。本文在研究了国内外大屏幕显示拼接技术的基础上,实现了独立投影的两幅图像在投影幕上拼接显示为一幅无缝的高分辨率的图像。满足了人们对高分辨率、大可视范围的展示设备的需求,同时实验器材仅需两台投影仪、两台PC机及一台摄像机,因此也满足了人们的低成本的需求。本文的主要工作分为以下两个重点： (1)几何校正寻找各坐标空间,投影仪空间、投影幕空间和摄像机空间,之间的矩阵转换关系,最终得到两投影仪投影显示区的位置关系参数,以及预畸变矩阵,对投影图像进行几何预处理,实现投影图像的几何配准。 (2)颜色校正主要分为两个方面,一是两台投影仪之间的颜色差异校正,二是两台投影仪重叠区域的颜色融合。在全局颜色校正部分,利用三次B样条理论,得到各投影仪的颜色传递函数,计算它们的公共色域,并对各投影仪颜色输入值进行校正,减小投影仪间的颜色差异。颜色融合部分,选取合适的融合函数,对图像的重叠部分进行渐入渐出式衰减融合处理,消除高亮效应,实现无缝拼接的目的。本文的主要创新改进工作有： (1)图像融合过程中,对图像重叠部分的alpha通道赋值时,不是利用投影幕上左右投影区的重叠信息,而是直接利用原始图像的固定重叠像素信息,计算融合函数的结果,赋值给alpha通道,从而避免了计算不规则的投影重叠区。 (2)强调了重叠区和融合区两个不同的概念,突出在图像融合过程中计算融合函数时两者的区别。恰当的选择融合区的大小,更好地消除图像重叠部分的高亮效应,达到无缝拼接的目的,使投影图像整体效果在视觉上颜色更加一致均匀。由于目前大屏幕显示系统昂贵的价格,以及其复杂的操作流程,使得人们对低成本的大屏幕拼接显示系统的需求越来越紧迫。本文正是从这一角度出发,在实验中选取成本低、操作简单,为普通实验室所有的一些仪器,来进行低成本的多通道大屏幕图像的无缝拼接技术研究。通过长时间的研究与实验,取得了一定的实验结果,并再次证实了基于普通摄像机的低成本的多通道图像无缝拼接的实用性与重要性。
[Abstract]:In recent years, with the continuous development of projection display technology, large screen splicing technology has been widely used in virtual simulation training, command and control, industrial manufacturing design, scientific research and complex decision-making processes, and in advertising, exhibition and display, The application of entertainment is becoming more and more popular. At present, the large screen display system widely used is high performance projector, its cost is very expensive, it is difficult to popularize. It has certain practical value and practical significance to study the high resolution large screen display system based on multiple projectors based on camera. This paper studies the technology of large screen display splicing at home and abroad. The two images of independent projection are spliced into a seamless high resolution image on the projection screen. To meet the needs of high resolution, large visual range display equipment, and experimental equipment only two projectors, two PCs and a camera, The main work of this paper is as follows: 1) the matrix transformation relationship between coordinate space, projector space, projection screen space and camera space. Finally, the position relation parameters of the projection display area of the two projectors and the predistortion matrix are obtained. The geometric preprocessing of the projection image is carried out to realize the geometric registration of the projection image. The color correction is mainly divided into two aspects. One is the color difference correction between the two projectors, the other is the color fusion of the overlapping area between the two projectors. In the global color correction part, the color transfer function of each projector is obtained by using the cubic B-spline theory. The common color gamut is calculated and the color input values of each projector are corrected to reduce the color difference between the projectors. In the part of color fusion, the suitable fusion function is selected, and the overlapping part of the image is processed by gradual in and out attenuation fusion, which eliminates the highlight effect and realizes the purpose of seamless stitching. The main innovation and improvement work of this paper are as follows: 1) in the process of image fusion, When the alpha channel of the overlapping part of the image is assigned, the overlapping information of the left and right projection areas on the projection screen is not used, but the fixed overlapping pixel information of the original image is directly used to calculate the result of the fusion function and assign the value to the alpha channel. In order to avoid the calculation of irregular projection overlapped region, we emphasize the two different concepts of overlapping region and fusion region, and emphasize the difference between them when calculating fusion function in image fusion process. Choosing the size of the fusion area properly to eliminate the highlight effect of the overlapped part of the image better, and achieve the purpose of seamless stitching. Because of the high price of large screen display system and its complicated operation flow, the demand of low cost large screen splicing display system is more and more urgent. From this point of view, this paper selects some instruments of low cost and simple operation, which are all owned by ordinary laboratory, to study the seamless stitching technology of multi-channel large screen images with low cost. After a long time of research and experiment, some experimental results have been obtained, and the practicability and importance of seamless multichannel image stitching based on common video camera have been confirmed again.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TP391.41

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