多投影及移动投影增强现实技术
|
摘要
增强现实是虚拟现实中的一项前沿技术。随着视觉相关的前沿技术的发展和相机,投影仪等硬件设备的成本越来越低,基于投影仪相机的系统将会带来很多其他显示设备所不具备的乐趣,最终改变人们的生活。投影显示技术的优势是理论上可成像在任意表面。通过增加投影仪的数量,可近乎无限的扩充可视范围,任意的显示分辨率,来获得沉浸式的用户体验,这是目前国内外增强现实技术研究的一个热点。
本文主要研究多投影仪条件下的增强现实技术。目前关于光度补偿的研究基于单投影仪,可在带有纹理和颜色的表面上进行补偿投影显示。在多投影系统中,由于多投影带来了重叠区域的光度不一致性,相机的每个像素覆盖的区域增大等问题,直接采样单投影的光度补偿技术,容易致使光度补偿失败或效果不够理想。现有的光度一致性算法,主要是对投影重叠区域进行光度衰减,但实际的效果有点矫枉过正,重叠区域反而过暗。而在移动投影方面,动态光补偿这个领域基本还未有前人涉足。
针对上文的前两个问题,本文提出了一整套的解决方案,构想并实现了一个单相机多投影仪系统,该系统采用一台相机采样环境数据?和投影仪参数,用多台投影仪来共同显示。在第三章,本文将依次介绍系统几何校正,光度补偿和光度一致这三大功能的原理和实现。主要阐述投影仪图像空间与相机空间的映射关系的建立,单投影补偿的模型,投影环境参数的获取和整个补偿算法的流程,以及多台投影仪间重叠区域像素衰减系数的计算方法。在第五章,本文将阐述整个系统架构的设计思路,并在最后给出采用了多投影补偿的效果,融合的效果,以及最终整合的效果。这些图片效果和数据分析表明了本系统很好的实现了上述三大功能。
第四章将介绍对移动投影的研究。第三章涉及的内容是静态的,其中背景,环境光,投影仪外部参数,用户视点都假设是不变的。本章将研究这些参数动态变化的条件下,如何获取变化的信息和实现更有意思的应用。其中,环境光补偿是前人所没有涉及的领域,本文给出了可行的计算模型和补偿中的要点,在第五章会给出试验效果。而如果能跟踪投影仪外部参数,用户视点的变化则可以带来更有趣的应用。第四章第二节将研究一个基于跟踪视点和移动投影仪的,能够投影虚拟三维物体的渲染系统所涉及的算法和系统架构。
本文主要的创新点有:
1单相机多投影仪系统实现了多台投影仪的几何校正,光度补偿和光度一致,即能够将图像投影到一个带纹理的复杂曲面上,为某个固定视点的用户提供一个几何规则的,补偿了背景纹理的统一图像,就像一台具备大范围投影能力的投影仪投出的单幅大图像。
2单相机多投影仪系统采用一种方便快捷的迭代方式来提高投影表面反射率参数的获取精度,在使用多投影仪单相机的同时可以达到与单投影媲美的补偿效果,仅需对投影区域增加捕捉4-6幅图像。并且针对多投影补偿计算量增大的问题,通过GPU加速加以解决。
3单相机多投影仪系统对多投影仪重叠区域的融合算法做了改进,解决了原有方法重叠区域过渡明显的问题。
4首次给出了单投影单相机条件下的动态光补偿方法,该方法具有自适应的特点,补偿效果明显。
Augmented Reality is a cutting-edge research field in virtual reality. Nowadays with the development of visual computation technology and price keep going down with the projector and camera we are able to create a cheap camera-projector system with the ability which can’t be achieved by other kinds of display devices. The projection device is superior to other displaying device in the way that it can project its image onto any surfaces. And by enlarging the number of the projectors, you can have a visible range with almost unlimited expansion , so to get immersed user experience.
Single projector radiometric compensation techniques have already made it possible for a projector to display on ordinary surface with colors and textures. However, when applying these methods to multi-projectors, the overlapping area of multi-projectors will bring inconsistence in intensity, also the result will not be as good as with a single projector and will lead to failure of the compensation. Also there is problem with the photometric consistency method for multi-projectors, when applying these methods, the overlapping area seems to be darker than other areas. Also, regarding to the area of compensation of dynamic environment light, there is no previous study available about this subject yet.
This paper presents a multi-projector and camera system, with the ability of geometry correction, radiometric compensation and photometric consistency, solve the first two problems mentioned. Our system is made of two or four projectors with the same type, one camera and three or more computers. We will explain the details of the functions of the system fully in chapter 3.It will mainly focus on subject of how to establish the mapping between the projector and the camera, the model of the single projector compensation, how to get the parameter of the environment, our improvement for the muti-projector system and the how to calculate the attenuation coefficient in the overlapping area between projectors. And giving a full display and discuss of the experiment result in chapter 5,we were quite sure that this system has achieved its goal.
Also we provide a model and solution for compensation of dynamic environment light. Finally, we have studied and provided the structure and implementation of a mobile projector rendering system for further use. We provide the experiment result in chapter 5.
The main contributions are:
(1) We provided a whole package of solution for a multi-projector and camera system, which is able to project onto any complex surfaces with pattern on it, and to provide the user with an integrated regular image without any obvious pattern on it.
(2) We use a convenient and iterative way to obtain more precise parameter of the reflection property of the projecting surface, which need taking only two or more pictures of the projecting-surface, so that it can provide much better compensation result. We provide pictures with only one compensation compared with pictures with both compensation and 2 to 5 times iteration,also you can see the blending result with the method in compared with the result with our improvement. Also since we have to compute the data for each projector, we ported the code the CUDA to achieve better performance.
(3) We have also improved the blending results of the overlapping area of multi-projectors and thus provide a unified solution for photometric consistency problem when displaying on non-optimized surfaces with multi-projectors.
(4) We have provided a solution for dynamic light compensation for the first time in this area, although the result is not stable as time passes by, it is very obvious the light has been compensated.
本文主要研究多投影仪条件下的增强现实技术。目前关于光度补偿的研究基于单投影仪,可在带有纹理和颜色的表面上进行补偿投影显示。在多投影系统中,由于多投影带来了重叠区域的光度不一致性,相机的每个像素覆盖的区域增大等问题,直接采样单投影的光度补偿技术,容易致使光度补偿失败或效果不够理想。现有的光度一致性算法,主要是对投影重叠区域进行光度衰减,但实际的效果有点矫枉过正,重叠区域反而过暗。而在移动投影方面,动态光补偿这个领域基本还未有前人涉足。
针对上文的前两个问题,本文提出了一整套的解决方案,构想并实现了一个单相机多投影仪系统,该系统采用一台相机采样环境数据?和投影仪参数,用多台投影仪来共同显示。在第三章,本文将依次介绍系统几何校正,光度补偿和光度一致这三大功能的原理和实现。主要阐述投影仪图像空间与相机空间的映射关系的建立,单投影补偿的模型,投影环境参数的获取和整个补偿算法的流程,以及多台投影仪间重叠区域像素衰减系数的计算方法。在第五章,本文将阐述整个系统架构的设计思路,并在最后给出采用了多投影补偿的效果,融合的效果,以及最终整合的效果。这些图片效果和数据分析表明了本系统很好的实现了上述三大功能。
第四章将介绍对移动投影的研究。第三章涉及的内容是静态的,其中背景,环境光,投影仪外部参数,用户视点都假设是不变的。本章将研究这些参数动态变化的条件下,如何获取变化的信息和实现更有意思的应用。其中,环境光补偿是前人所没有涉及的领域,本文给出了可行的计算模型和补偿中的要点,在第五章会给出试验效果。而如果能跟踪投影仪外部参数,用户视点的变化则可以带来更有趣的应用。第四章第二节将研究一个基于跟踪视点和移动投影仪的,能够投影虚拟三维物体的渲染系统所涉及的算法和系统架构。
本文主要的创新点有:
1单相机多投影仪系统实现了多台投影仪的几何校正,光度补偿和光度一致,即能够将图像投影到一个带纹理的复杂曲面上,为某个固定视点的用户提供一个几何规则的,补偿了背景纹理的统一图像,就像一台具备大范围投影能力的投影仪投出的单幅大图像。
2单相机多投影仪系统采用一种方便快捷的迭代方式来提高投影表面反射率参数的获取精度,在使用多投影仪单相机的同时可以达到与单投影媲美的补偿效果,仅需对投影区域增加捕捉4-6幅图像。并且针对多投影补偿计算量增大的问题,通过GPU加速加以解决。
3单相机多投影仪系统对多投影仪重叠区域的融合算法做了改进,解决了原有方法重叠区域过渡明显的问题。
4首次给出了单投影单相机条件下的动态光补偿方法,该方法具有自适应的特点,补偿效果明显。
Augmented Reality is a cutting-edge research field in virtual reality. Nowadays with the development of visual computation technology and price keep going down with the projector and camera we are able to create a cheap camera-projector system with the ability which can’t be achieved by other kinds of display devices. The projection device is superior to other displaying device in the way that it can project its image onto any surfaces. And by enlarging the number of the projectors, you can have a visible range with almost unlimited expansion , so to get immersed user experience.
Single projector radiometric compensation techniques have already made it possible for a projector to display on ordinary surface with colors and textures. However, when applying these methods to multi-projectors, the overlapping area of multi-projectors will bring inconsistence in intensity, also the result will not be as good as with a single projector and will lead to failure of the compensation. Also there is problem with the photometric consistency method for multi-projectors, when applying these methods, the overlapping area seems to be darker than other areas. Also, regarding to the area of compensation of dynamic environment light, there is no previous study available about this subject yet.
This paper presents a multi-projector and camera system, with the ability of geometry correction, radiometric compensation and photometric consistency, solve the first two problems mentioned. Our system is made of two or four projectors with the same type, one camera and three or more computers. We will explain the details of the functions of the system fully in chapter 3.It will mainly focus on subject of how to establish the mapping between the projector and the camera, the model of the single projector compensation, how to get the parameter of the environment, our improvement for the muti-projector system and the how to calculate the attenuation coefficient in the overlapping area between projectors. And giving a full display and discuss of the experiment result in chapter 5,we were quite sure that this system has achieved its goal.
Also we provide a model and solution for compensation of dynamic environment light. Finally, we have studied and provided the structure and implementation of a mobile projector rendering system for further use. We provide the experiment result in chapter 5.
The main contributions are:
(1) We provided a whole package of solution for a multi-projector and camera system, which is able to project onto any complex surfaces with pattern on it, and to provide the user with an integrated regular image without any obvious pattern on it.
(2) We use a convenient and iterative way to obtain more precise parameter of the reflection property of the projecting surface, which need taking only two or more pictures of the projecting-surface, so that it can provide much better compensation result. We provide pictures with only one compensation compared with pictures with both compensation and 2 to 5 times iteration,also you can see the blending result with the method in compared with the result with our improvement. Also since we have to compute the data for each projector, we ported the code the CUDA to achieve better performance.
(3) We have also improved the blending results of the overlapping area of multi-projectors and thus provide a unified solution for photometric consistency problem when displaying on non-optimized surfaces with multi-projectors.
(4) We have provided a solution for dynamic light compensation for the first time in this area, although the result is not stable as time passes by, it is very obvious the light has been compensated.
引文
[1] Feiner, Steven, Blair MacIntyre, Marcus Haupt, Eliot Solomon. Windows on the World: 2D Windows for 3D Augmented Reality. Proceedings of UIST’93. 1993, 141–155
[2] Milgram, Paul, Haruo takemura, Akira Utsumi, Fumio Kishino. Augmented Real‐ity: A Class of Displays on the Reality Virtuality Continuum. SPIE Proceedings:Telemanipulator and Telepresence Technologies. 1995, vol. 2351, 282–292
[3] URL http://en.wikipedia.org/wiki/Augmented_reality
[4] Perry A. Appino, J. Bryan Lewis, Lawrence Koved, Daniel T. Ling, David A. Raben‐horst,Christopher F. Codella. An architecture for virtual worlds. Presence: Teleoper Virtual Environ. 1992, 1(1):1–17
[5] Christer Carlsson , Olof Hagsand. DIVE‐ A multi‐user virtual reality system. Virtual Reality Annual International Symposium. 1993, 394–400
[6] URL http://en.wikipedia.org/wiki/Virtual_reality
[7] R. Raskar, J. van Baar et al. iLamps: Geometrically Aware and Self‐configuring Projectors. ACM Transactions on Graphics (SIGGRAPH 2003). 2003, 22(3):809‐818
[8] Y.Chen, D. Clark et al. Automatic Alignment Of High‐Resolution Multi‐Projector Displays Using An Un‐Calibrated Camera. Proceeding of IEEE Visualization 2000. 2000:125‐130
[9] K. Li, Y. Chen et al. Early Experiences and Challenges in Building and Using a Scalable Display Wall System. IEEE Computer Graphics and Applications. 2000, 20(4):671‐680
[10] R. Raskar, J. van Baar, J. Chai. A Low Cost Projector Mosaic with Fast Registration. Fifth International Conference on Computer Vision (ACCV02). 2002
[11] R. Yang, D. Gotz et al. PixelFlex: A Reconfigurable Multi‐Projector Display System. Proceeding of IEEE Visualization. 2001:167‐174
[12] H. Chen, R. Sukthankar, G. Wallace. Scalable Alignment of Large‐Format Multi‐Projector Displays Using Camera Homography Trees. Proceedings of IEEE Visualization 2002. 2002:339‐346
[13] R. Raskar, G. Welch et al. The Office of the Future: A Unified Approach to Image‐Based Modeling and Spatially Immersive Displays. Computer Graphics. 1998, 32(Annual Conference Series):179‐188
[14] Michael Brown, Aditi Majumder, Ruigang Yang. Camera‐Based Calibration Techniques for Seamless Multi‐Projector Displays. IEEE Transactions on Visualization and Computer Graphics. 2005, 11(2):193‐206
[15] R. Raskar, G. Welch, H. Fuchs. Spatially Augmented Reality. First International Workshop on Augmented Reality. Nov. 1998
[16] R. Raskar. Immersive Planar Display using Roughly Aligned Projectors. Proceeding of IEEE VR 2000. 2000:109‐116
[17] R. Raskar, G. Welch, H. Fuchs. Seamless Projection Overlaps using Image Warping and Intensity Blending. Proc. of 4th International Conference on Virtual Systems and Multimedia. 1998
[18] R. Surati. Scalable Self‐Calibrating Display Technology for Seamless Large‐Scale Displays[dissertation]. Department of Computer Science, Massachusetts Institute of Technology. 1998
[19] Shree K. Nayar, Harish Peri, Michael D. Grossberg and Peter N. Belhumeur.“A Projection System with Radiometric Compensation for Screen Imperfections”. In IEEE International Workshop on Projector‐Camera Systems, Oct. 2003
[20] Bimber, O., Coriand, F., Kleppe, A., Bruns, E., Zollmann, S., & Langlotz, T. (2005c).“Superimposing Pictorial Artwork with Projected Imagery”. IEEE MultiMedia. 12(1), 16‐26
[21] G. Wallace, H. Chen, K. Li. Color Gamut Matching for Tiled Display Walls. Immersive Projection Technology Workshop. 2003
[22] M. Bern, D. Eppstein. Optimized color gamuts for tiled displays. ACM Computing Research Repository. 2003
[23] A. Majumder, R. Stevens. Color Nonuniformity in Projection‐Based Displays: Analysis and Solutions. IEEE Transactions on Visualization and Computer Graphics. 2003, 10(2)
[24] A. Majumder, Z. He et. al. Achieving Color Uniformity Across Multi‐Projector Displays. Proceedings of IEEE Visualization. 2000
[25] A. Majumder, R. Stevens. LAM: Luminance Attenuation Map for Photometric Uniformity in Projection Based Displays. Proceedings of ACM Virtual Reality and Software Technology. 2002
[26] A. Majumder. Contrast enhancement of multi‐displays using human contrast sensitivity, Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (CVPR2005). 2005:377‐382
[27] Aditi Majumder, Rick Stevens. Perceptual Photometric Seamlessness in Projection‐Based Tiled Displays. ACM Transactions on Graphics. 2001
[28] RFIG Lamps: Interacting with a Self‐Describing World via Photosensing Wireless Tags and Projectors Ramesh Raskar ,Paul Beardsley ,Jeroen van
[29] Interaction Using a Handheld Projector.IEEE Computer Graphics and Applications. Vol. 25, no. 1, pp. 39‐43. Jan.‐Feb. 2005
[30] Surround‐Screen Projection‐Based Virtual Reality:The Design and Implementation of the CAVE Carolina Cruz‐Neira Daniel J. Sandin,Thomas A. DeFanti,Electronic Visualization Laboratory (EVL),The University of Illinois at Chicago
[31] S.K.Nayar, H. Peri, M. D. Grossberg, and P. N. Belhumeur. A projection system with radiometric compensation for screen imperfections[A]. In IEEE International Workshop on Projector‐Camera Systems[C], 2003.
[32]谭晓军郭志豪蒋芝.基于对称性特征的棋盘方格角点自动检测算法[J].计算机应用, 2008,28(6): 1540‐1542
[33] Paul E. Debevec, Jitendra Malik. Recovering high dynamic range radiance maps from photographs. Proc. of ACM SIGGRAPH 1997. 1997, 369–378
[34] Ruigang Yang, David Gotz, Justin Hensley, Herman Towles, Michael S. Brown. Pix‐ elFlex: a recon gurable multi‐projector display system. Proc. of IEEE Visualization.2001, 167–174
[35] Aditi Majumder, Rick Stevens. LAM: luminance attenuation map for photometric uniformity in projection based displays. Proc. of VRST. ACM, 2002, 147–154
[36] Andrew Raij, Gennette Gill, Aditi Majumder, Herman Towles, Henry Fuchs. Pix‐elflex2: A Comprehensive, Automatic, Casually‐Aligned Multi‐Projector Display.IEEE International Workshop on Projector‐Camera Systems. 2003
[37] Michael D. Grossberg, Harish Peri, Shree K. Nayar, Peter N. Belhumeur. Making One Object Look Like Another: Controlling Appearance Using a Projector‐Camera System [A], IEEE Computer Society Conference on Computer Vision and Pattern Recognition [C], vol. 1, pp. 452‐459, 2004
[38] FUJII, K., GROSSBERG, M. D., AND NAYAR, S. K. A Projector‐Camera System with Real‐Time Photometric Adaptation for Dynamic Environments[A], Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) [C]‐ Volume 1, p.814‐821, June 20‐26, 2005
[39] Xinli Chen, Xubo Yang, Shuangjiu Xiao, Meng Li. Color Mixing Property of a Projector‐Camera System[A] International Conference on Computer Graphics and Interactive Techniques. Proceedings of the 5th ACM/IEEE International Workshop on Projector camera systems[C],2008
[40]深入浅出谈CUDAhttp://blog.csdn.net/gudaoqianfu/archive/2009/02/19/3912247.aspx
[41] CUDA shared memory使用‐‐‐‐‐‐GPU的革命http://blog.csdn.net/OpenHero/archive/2009/02/14/3890578.aspx
[42] Kahan_summation_algorithm .http://en.wikipedia.org/wiki/Kahan_summation_algorithm
[43] P Sloan and J Kautz and J Snyder. Precomputed radiance transfer for real‐time rendering in dynamic, low‐frequency lighting environments. In SIGGRAPH 2002.
[44] Martin Fuchs and Hendrik P A Lensch and Hans‐Peter Seidel. Reflectance from images: A model‐based approach for human faces. In IEEE Transactions on Visualization and Computer Graphics, pp. 296‐305, 2005.
[45] P. Debevec and J. Malik. Recovering High Dynamic Range Radiance Maps from Photographs. In IEEE Transactions on Visualization and Computer Graphics, 1997.
[2] Milgram, Paul, Haruo takemura, Akira Utsumi, Fumio Kishino. Augmented Real‐ity: A Class of Displays on the Reality Virtuality Continuum. SPIE Proceedings:Telemanipulator and Telepresence Technologies. 1995, vol. 2351, 282–292
[3] URL http://en.wikipedia.org/wiki/Augmented_reality
[4] Perry A. Appino, J. Bryan Lewis, Lawrence Koved, Daniel T. Ling, David A. Raben‐horst,Christopher F. Codella. An architecture for virtual worlds. Presence: Teleoper Virtual Environ. 1992, 1(1):1–17
[5] Christer Carlsson , Olof Hagsand. DIVE‐ A multi‐user virtual reality system. Virtual Reality Annual International Symposium. 1993, 394–400
[6] URL http://en.wikipedia.org/wiki/Virtual_reality
[7] R. Raskar, J. van Baar et al. iLamps: Geometrically Aware and Self‐configuring Projectors. ACM Transactions on Graphics (SIGGRAPH 2003). 2003, 22(3):809‐818
[8] Y.Chen, D. Clark et al. Automatic Alignment Of High‐Resolution Multi‐Projector Displays Using An Un‐Calibrated Camera. Proceeding of IEEE Visualization 2000. 2000:125‐130
[9] K. Li, Y. Chen et al. Early Experiences and Challenges in Building and Using a Scalable Display Wall System. IEEE Computer Graphics and Applications. 2000, 20(4):671‐680
[10] R. Raskar, J. van Baar, J. Chai. A Low Cost Projector Mosaic with Fast Registration. Fifth International Conference on Computer Vision (ACCV02). 2002
[11] R. Yang, D. Gotz et al. PixelFlex: A Reconfigurable Multi‐Projector Display System. Proceeding of IEEE Visualization. 2001:167‐174
[12] H. Chen, R. Sukthankar, G. Wallace. Scalable Alignment of Large‐Format Multi‐Projector Displays Using Camera Homography Trees. Proceedings of IEEE Visualization 2002. 2002:339‐346
[13] R. Raskar, G. Welch et al. The Office of the Future: A Unified Approach to Image‐Based Modeling and Spatially Immersive Displays. Computer Graphics. 1998, 32(Annual Conference Series):179‐188
[14] Michael Brown, Aditi Majumder, Ruigang Yang. Camera‐Based Calibration Techniques for Seamless Multi‐Projector Displays. IEEE Transactions on Visualization and Computer Graphics. 2005, 11(2):193‐206
[15] R. Raskar, G. Welch, H. Fuchs. Spatially Augmented Reality. First International Workshop on Augmented Reality. Nov. 1998
[16] R. Raskar. Immersive Planar Display using Roughly Aligned Projectors. Proceeding of IEEE VR 2000. 2000:109‐116
[17] R. Raskar, G. Welch, H. Fuchs. Seamless Projection Overlaps using Image Warping and Intensity Blending. Proc. of 4th International Conference on Virtual Systems and Multimedia. 1998
[18] R. Surati. Scalable Self‐Calibrating Display Technology for Seamless Large‐Scale Displays[dissertation]. Department of Computer Science, Massachusetts Institute of Technology. 1998
[19] Shree K. Nayar, Harish Peri, Michael D. Grossberg and Peter N. Belhumeur.“A Projection System with Radiometric Compensation for Screen Imperfections”. In IEEE International Workshop on Projector‐Camera Systems, Oct. 2003
[20] Bimber, O., Coriand, F., Kleppe, A., Bruns, E., Zollmann, S., & Langlotz, T. (2005c).“Superimposing Pictorial Artwork with Projected Imagery”. IEEE MultiMedia. 12(1), 16‐26
[21] G. Wallace, H. Chen, K. Li. Color Gamut Matching for Tiled Display Walls. Immersive Projection Technology Workshop. 2003
[22] M. Bern, D. Eppstein. Optimized color gamuts for tiled displays. ACM Computing Research Repository. 2003
[23] A. Majumder, R. Stevens. Color Nonuniformity in Projection‐Based Displays: Analysis and Solutions. IEEE Transactions on Visualization and Computer Graphics. 2003, 10(2)
[24] A. Majumder, Z. He et. al. Achieving Color Uniformity Across Multi‐Projector Displays. Proceedings of IEEE Visualization. 2000
[25] A. Majumder, R. Stevens. LAM: Luminance Attenuation Map for Photometric Uniformity in Projection Based Displays. Proceedings of ACM Virtual Reality and Software Technology. 2002
[26] A. Majumder. Contrast enhancement of multi‐displays using human contrast sensitivity, Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (CVPR2005). 2005:377‐382
[27] Aditi Majumder, Rick Stevens. Perceptual Photometric Seamlessness in Projection‐Based Tiled Displays. ACM Transactions on Graphics. 2001
[28] RFIG Lamps: Interacting with a Self‐Describing World via Photosensing Wireless Tags and Projectors Ramesh Raskar ,Paul Beardsley ,Jeroen van
[29] Interaction Using a Handheld Projector.IEEE Computer Graphics and Applications. Vol. 25, no. 1, pp. 39‐43. Jan.‐Feb. 2005
[30] Surround‐Screen Projection‐Based Virtual Reality:The Design and Implementation of the CAVE Carolina Cruz‐Neira Daniel J. Sandin,Thomas A. DeFanti,Electronic Visualization Laboratory (EVL),The University of Illinois at Chicago
[31] S.K.Nayar, H. Peri, M. D. Grossberg, and P. N. Belhumeur. A projection system with radiometric compensation for screen imperfections[A]. In IEEE International Workshop on Projector‐Camera Systems[C], 2003.
[32]谭晓军郭志豪蒋芝.基于对称性特征的棋盘方格角点自动检测算法[J].计算机应用, 2008,28(6): 1540‐1542
[33] Paul E. Debevec, Jitendra Malik. Recovering high dynamic range radiance maps from photographs. Proc. of ACM SIGGRAPH 1997. 1997, 369–378
[34] Ruigang Yang, David Gotz, Justin Hensley, Herman Towles, Michael S. Brown. Pix‐ elFlex: a recon gurable multi‐projector display system. Proc. of IEEE Visualization.2001, 167–174
[35] Aditi Majumder, Rick Stevens. LAM: luminance attenuation map for photometric uniformity in projection based displays. Proc. of VRST. ACM, 2002, 147–154
[36] Andrew Raij, Gennette Gill, Aditi Majumder, Herman Towles, Henry Fuchs. Pix‐elflex2: A Comprehensive, Automatic, Casually‐Aligned Multi‐Projector Display.IEEE International Workshop on Projector‐Camera Systems. 2003
[37] Michael D. Grossberg, Harish Peri, Shree K. Nayar, Peter N. Belhumeur. Making One Object Look Like Another: Controlling Appearance Using a Projector‐Camera System [A], IEEE Computer Society Conference on Computer Vision and Pattern Recognition [C], vol. 1, pp. 452‐459, 2004
[38] FUJII, K., GROSSBERG, M. D., AND NAYAR, S. K. A Projector‐Camera System with Real‐Time Photometric Adaptation for Dynamic Environments[A], Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) [C]‐ Volume 1, p.814‐821, June 20‐26, 2005
[39] Xinli Chen, Xubo Yang, Shuangjiu Xiao, Meng Li. Color Mixing Property of a Projector‐Camera System[A] International Conference on Computer Graphics and Interactive Techniques. Proceedings of the 5th ACM/IEEE International Workshop on Projector camera systems[C],2008
[40]深入浅出谈CUDAhttp://blog.csdn.net/gudaoqianfu/archive/2009/02/19/3912247.aspx
[41] CUDA shared memory使用‐‐‐‐‐‐GPU的革命http://blog.csdn.net/OpenHero/archive/2009/02/14/3890578.aspx
[42] Kahan_summation_algorithm .http://en.wikipedia.org/wiki/Kahan_summation_algorithm
[43] P Sloan and J Kautz and J Snyder. Precomputed radiance transfer for real‐time rendering in dynamic, low‐frequency lighting environments. In SIGGRAPH 2002.
[44] Martin Fuchs and Hendrik P A Lensch and Hans‐Peter Seidel. Reflectance from images: A model‐based approach for human faces. In IEEE Transactions on Visualization and Computer Graphics, pp. 296‐305, 2005.
[45] P. Debevec and J. Malik. Recovering High Dynamic Range Radiance Maps from Photographs. In IEEE Transactions on Visualization and Computer Graphics, 1997.