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4D frequency analysis of computational cameras for depth of field extension

Anat Levin, Samuel W. Hasinoff, Paul Green, Frédo Durand, William T. Freeman
2009 ACM Transactions on Graphics  
We analyze defocus kernels in the 4D light field space and show that in the frequency domain, only a low-dimensional 3D manifold contributes to focus.  ...  We have built a prototype lattice-focal lens and present extended depth of field results.  ...  The Fourier optics OTF of a wavefront coding lens can be computed as well, and we refer the reader to [Zhang and Levoy 2009; Dowski and Cathey 1995] for derivation.  ... 
doi:10.1145/1531326.1531403 fatcat:6g2xemm4rndhdar3xvilmtsk5q

4D frequency analysis of computational cameras for depth of field extension

Anat Levin, Samuel W. Hasinoff, Paul Green, Frédo Durand, William T. Freeman
2009 ACM SIGGRAPH 2009 papers on - SIGGRAPH '09  
We analyze defocus kernels in the 4D light field space and show that in the frequency domain, only a low-dimensional 3D manifold contributes to focus.  ...  We have built a prototype lattice-focal lens and present extended depth of field results.  ...  The Fourier optics OTF of a wavefront coding lens can be computed as well, and we refer the reader to [Zhang and Levoy 2009; Dowski and Cathey 1995] for derivation.  ... 
doi:10.1145/1576246.1531403 fatcat:hs3w6hsq5jgctfiqodn7snciui

Light field image denoising using a linear 4D frequency-hyperfan all-in-focus filter

Donald G. Dansereau, Daniel L. Bongiorno, Oscar Pizarro, Stefan B. Williams, Charles A. Bouman, Ilya Pollak, Patrick J. Wolfe
2013 Computational Imaging XI  
We show that the light field of a Lambertian scene has a 4D hyperfan-shaped frequency-domain region of support at the intersection of a dual-fan and a hypercone.  ...  Computational photography offers a promising solution in the form of the light field camera, which by capturing redundant information offers an opportunity for elegant noise rejection.  ...  Acknowledgment This work is supported in part by the Australian Centre for Field Robotics, the New South Wales State Government, The University of Sydney, and the Australian Government's International  ... 
doi:10.1117/12.2002239 dblp:conf/cimaging/DansereauBPW13 fatcat:vucjaf7lq5h3de2yifvuudbd7i

Light Field Blind Motion Deblurring

Pratul P. Srinivasan, Ren Ng, Ravi Ramamoorthi
2017 2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)  
By analyzing the motion-blurred light field in the primal and Fourier domains, we develop intuition into the effects of camera motion on the light field, show the advantages of capturing a 4D light field  ...  instead of a conventional 2D image for motion deblurring, and derive simple methods of motion deblurring in certain cases.  ...  Previous work has demonstrated the benefits of lifting problems in computer vision, computer graphics, and computational photography into the 4D light field space.  ... 
doi:10.1109/cvpr.2017.253 dblp:conf/cvpr/SrinivasanNR17 fatcat:gcw3qplfpjeg5ftmhkozy7ggzq

Dappled photography

Ashok Veeraraghavan, Ramesh Raskar, Amit Agrawal, Ankit Mohan, Jack Tumblin
2007 ACM SIGGRAPH 2007 papers on - SIGGRAPH '07  
This partial encoding of 4D ray-space data enables editing of image contents by depth, yet does not require computational recovery of the complete 4D light field.  ...  Abstract We describe a theoretical framework for reversibly modulating 4D light fields using an attenuating mask in the optical path of a lens based camera.  ...  Acknowledgements We thank the anonymous reviewers and several members of MERL for their suggestions.  ... 
doi:10.1145/1275808.1276463 fatcat:xdqjsg55kzdmlalpk44ph5kofu

Light Field Blind Motion Deblurring [article]

Pratul P. Srinivasan, Ren Ng, Ravi Ramamoorthi
2017 arXiv   pre-print
By analyzing the motion-blurred light field in the primal and Fourier domains, we develop intuition into the effects of camera motion on the light field, show the advantages of capturing a 4D light field  ...  instead of a conventional 2D image for motion deblurring, and derive simple methods of motion deblurring in certain cases.  ...  Previous work has demonstrated the benefits of lifting problems in computer vision, computer graphics, and computational photography into the 4D light field space.  ... 
arXiv:1704.05416v1 fatcat:cwx2ivx6rfha7cdqubfrryqf7e

Computational Photography [article]

Ramesh Raskar, Jack Tumblin, Ankit Mohan, Amit Agrawal, Yuanzen Li
2006 Eurographics State of the Art Reports  
Unbounded dynamic range, variable focus, resolution, and depth of field, hints about shape, reflectance, and lighting, and new interactive forms of photos that are partly snapshots and partly videos are  ...  Computational photography combines plentiful computing, digital sensors, modern optics, actuators, probes and smart lights to escape the limitations of traditional film cameras and enables novel imaging  ...  The theory enables one to compute photographs focused at different depths more quickly from the 4D light field data.  ... 
doi:10.2312/egst.20061051 fatcat:6ig2c522qve3bejhvvb4jemipu

Light Field Image Processing: An Overview

Gaochang Wu, Belen Masia, Adrian Jarabo, Yuchen Zhang, Liangyong Wang, Qionghai Dai, Tianyou Chai, Yebin Liu
2017 IEEE Journal on Selected Topics in Signal Processing  
for light field display, and computer vision applications of light field data.  ...  On the one hand, this higher-dimensional representation of visual data offers powerful capabilities for scene understanding, and substantially improves the performance of traditional computer vision problems  ...  [66] provided code for light field analysis in terms of both depth estimation and light field super-resolution. Tao et al.  ... 
doi:10.1109/jstsp.2017.2747126 fatcat:rvsfzvdxbbf4zesqdkaj3cseza

Depth from Combining Defocus and Correspondence Using Light-Field Cameras

Michael W. Tao, Sunil Hadap, Jitendra Malik, Ravi Ramamoorthi
2013 2013 IEEE International Conference on Computer Vision  
We then show how to combine the two cues into a high quality depth map, suitable for computer vision applications such as matting, full control of depth-of-field, and surface reconstruction.  ...  Light-field cameras have recently become available to the consumer market.  ...  We are grateful for the support from Nokia, Samsung, and Adobe.  ... 
doi:10.1109/iccv.2013.89 dblp:conf/iccv/TaoHMR13 fatcat:ptag5qxxkvgldmeaoi7iyo4whu

Computational Photography [article]

Ramesh Raskar, Jack Tumblin, Ankit Mohan, Amit Agrawal, Yuanzen Li
2007 Eurographics State of the Art Reports  
Unbounded dynamic range, variable focus, resolution, and depth of field, hints about shape, reflectance, and lighting, and new interactive forms of photos that are partly snapshots and partly videos are  ...  Computational photography combines plentiful computing, digital sensors, modern optics, actuators, probes and smart lights to escape the limitations of traditional film cameras and enables novel imaging  ...  Pick the rays you need for ANY camera outside. --2D surface of cameras, 2D surface of cameras, + + 2D 2D ray set for each camera, ray set for each camera, 4D set of rays. 4D set of rays. 4-D Illumination  ... 
doi:10.2312/egt.20071066 fatcat:btr4b2hrszegnhrukfnwe7i7oe

An analysis of color demosaicing in plenoptic cameras

Zhan Yu, Jingyi Yu, A. Lumsdaine, T. Georgiev
2012 2012 IEEE Conference on Computer Vision and Pattern Recognition  
A plenoptic camera captures the 4D radiance about a scene. Recent practical solutions mount a microlens array on top of a commodity SLR to directly acquire these rays.  ...  In this paper, we develop a simple but effective technique for improving the image resolution of the plenoptic camera by maneuvering the demosaicing process.  ...  Extended Depth of Field Another popular application of our method is the extended depth of field photography.  ... 
doi:10.1109/cvpr.2012.6247764 dblp:conf/cvpr/YuYLG12 fatcat:y4bmoqtgx5acrihs6r63lkcu2u

Shield fields

Douglas Lanman, Ramesh Raskar, Amit Agrawal, Gabriel Taubin
2008 ACM Transactions on Graphics  
We first describe the properties of shield fields in the frequency-domain and briefly analyze the "forward" problem of efficiently computing cast shadows.  ...  (Left) The shield field camera, containing: an array of point lights, an object for reconstruction, and a large-format, mask-based light field camera.  ...  Acknowledgements We thank the anonymous reviewers for their useful suggestions, John Barnwell for assisting in the construction of the prototype system, Takafumi Aoki for preparing the video, and Jay Thornton  ... 
doi:10.1145/1409060.1409084 fatcat:gqabgte2ynh73pdywnfo5t6wpm

Shield fields

Douglas Lanman, Ramesh Raskar, Amit Agrawal, Gabriel Taubin
2008 ACM SIGGRAPH Asia 2008 papers on - SIGGRAPH Asia '08  
We first describe the properties of shield fields in the frequency-domain and briefly analyze the "forward" problem of efficiently computing cast shadows.  ...  (Left) The shield field camera, containing: an array of point lights, an object for reconstruction, and a large-format, mask-based light field camera.  ...  Acknowledgements We thank the anonymous reviewers for their useful suggestions, John Barnwell for assisting in the construction of the prototype system, Takafumi Aoki for preparing the video, and Jay Thornton  ... 
doi:10.1145/1457515.1409084 fatcat:772fghym4bfcbinr3iet5lunae

An overview of computational photography

JinLi Suo, XiangYang Ji, QiongHai Dai
2012 Science China Information Sciences  
, e.g. depth of field, dynamic range; and (iii) the sampling subspaces of visual scenes in the real world.  ...  As a loose description, computational photography accounts for studies for the extension of film-like photography and digital photography, which both capture only a 2D projection of visual scenes.  ...  [6, 72] , who designed mask enhanced cameras to heterodyne the band-limited light fields in the frequency domain for refocusing; Ng [32] , who analyzed the 4D light field captured by a lenslet based  ... 
doi:10.1007/s11432-012-4587-6 fatcat:pfndsz4n6bgbbotzx5m2sq4hvm

Variable Aperture Light Field Photography: Overcoming the Diffraction-Limited Spatio-Angular Resolution Tradeoff

Julie Chang, Isaac Kauvar, Xuemei Hu, Gordon Wetzstein
2016 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)  
In this paper, we analyze fundamental resolution limits of light field cameras in the diffraction limit.  ...  With this work, we hope to advance our understanding of the resolution limits of light field photography and develop practical computational imaging systems to overcome them.  ...  Acknowledgments We thank Marc Levoy for fruitful discussions. J. C. and I. K. were NSF Graduate Research Fellowship. X. H. was supported by the NSF of China, awards #61327902 and #61120106003.  ... 
doi:10.1109/cvpr.2016.406 dblp:conf/cvpr/ChangKHW16 fatcat:pbtncerja5hfjc2pzgxrldaijy
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