Filters








144 Hits in 4.7 sec

Smooth Reconstruction and Compact Representation of Reflectance Functions for Image-based Relighting [article]

Vincent Masselus, Pieter Peers, Philip Dutré, Yves D. Willemsy
2004 Symposium on Rendering  
In this paper we present a new method to reconstruct reflectance functions for image-based relighting.  ...  Our method improves on visual quality in comparison with previous image-based relighting methods, especially when animated incident illumination is used.  ...  Acknowledgments We would like to thank Frank Suykens for proofreading the paper. This work was partially supported by FWO Grant #G.0354.00 and K.U.Leuven Grant #OT/01-34.  ... 
doi:10.2312/egwr/egsr04/287-298 fatcat:4r3xjd3sr5g37o5glotm6j3mue

All-frequency shadows using non-linear wavelet lighting approximation

Ren Ng, Ravi Ramamoorthi, Pat Hanrahan
2003 ACM Transactions on Graphics  
For accurate rendering, using non-linear wavelets is an order of magnitude faster than using linear spherical harmonics, the current best technique.  ...  We obtain further compression by encoding the light transport matrix sparsely but accurately in the same basis.  ...  , Kekoa Proudfoot and Eric Chan for help with writing and code; and Peter Schröder and Gene Golub for advice.  ... 
doi:10.1145/882262.882280 fatcat:td7n6zwl2rg5zlsd5pdtqf3isy

All-frequency shadows using non-linear wavelet lighting approximation

Ren Ng, Ravi Ramamoorthi, Pat Hanrahan
2003 ACM SIGGRAPH 2003 Papers on - SIGGRAPH '03  
For accurate rendering, using non-linear wavelets is an order of magnitude faster than using linear spherical harmonics, the current best technique.  ...  We obtain further compression by encoding the light transport matrix sparsely but accurately in the same basis.  ...  , Kekoa Proudfoot and Eric Chan for help with writing and code; and Peter Schröder and Gene Golub for advice.  ... 
doi:10.1145/1201775.882280 fatcat:onagab3hnfgmffpnh3xrybcxlu

4D compression and relighting with high-resolution light transport matrices

Ewen Cheslack-Postava, Nolan Goodnight, Ren Ng, Ravi Ramamoorthi, Greg Humphreys
2007 Proceedings of the 2007 symposium on Interactive 3D graphics and games - I3D '07  
This paper presents a method for efficient compression and relighting with high-resolution, precomputed light transport matrices.  ...  Combined with a GPU-based precomputation pipeline, this results in an image and geometry relighting system that performs significantly better than 2D compression techniques, on average 2x-3x better in  ...  Transposing the matrix makes data access cache-coherent and further allows us to store the matrix as compressed, wavelet transformed images for efficient relighting.  ... 
doi:10.1145/1230100.1230115 dblp:conf/si3d/Cheslack-PostavaGNRH07 fatcat:ez3xd23t7zdnjhwjam4w4sqe4i

Compression of illumination-adjustable images

Tien-Tsin Wong, Chi-Sing Leung
2003 IEEE transactions on circuits and systems for video technology (Print)  
Keywords Image-based modeling and rendering, image-based relighting, multimedia application, data compression, spherical harmonic transform, wavelet transform.  ...  To relight the image-based scenery, the scene must be captured under various illumination conditions. This drastically increases the data volume. Hence, data compression is a must.  ...  PSNR vs. bit rate for wavelet compression. Figure 10 visually compares the images generated from the compressed data with various bit rates.  ... 
doi:10.1109/tcsvt.2003.817628 fatcat:hb4l77kpirdi3b456saas3xsai

Real-time triple product relighting using spherical local-frame parameterization

Wan-Chun Ma, Chun-Tse Hsiao, Ken-Yi Lee, Yung-Yu Chuang, Bing-Yu Chen
2006 The Visual Computer  
The use of spherical wavelets avoids uneven sampling and energy normalization of cubical parameterization.  ...  In addition, it greatly reduces the data size compared to storing BRDFs with respect to the global frame.  ...  Acknowledgements The authors would like to thank Peter Pon for his suggestions on GPU programming.  ... 
doi:10.1007/s00371-006-0064-9 fatcat:ds2hkzxyuzd4tphndnuny2bawq

Real-time editing and relighting of homogeneous translucent materials

Rui Wang, Ewen Cheslack-Postava, Rui Wang, David Luebke, Qianyong Chen, Wei Hua, Qunsheng Peng, Hujun Bao
2008 The Visual Computer  
To reduce the PRT data size, we compress both the illumination and spatial dimensions using efficient nonlinear wavelets.  ...  We present a novel method for accurate rendering and relighting of translucent materials that also enables real-time editing and manipulation of homogeneous diffuse BSSRDFs.  ...  Due to the speed and efficiency of the wavelet transform, we achieve fast precomputation at less than 2 h for all test scenes, and 3-4× speed up in relighting performance compared with no spatial compression  ... 
doi:10.1007/s00371-008-0237-9 fatcat:oi3zpfaygzd2vihgnuzkuheflm

Precomputation-Based Rendering

Ravi Ramamoorthi
2007 Foundations and Trends in Computer Graphics and Vision  
On the other hand, real-time rendering often fixes the object geometry and other attributes, such as relighting a static image for lighting design.  ...  In this survey, we describe the mathematical foundations, history, current research and future directions for precomputation-based rendering.  ...  Finally, I wish to thank the NSF for supporting my work on precomputation-based rendering with two grants (jointly with Henrik Wann Jensen), # 0305322 Acknowledgments 359 and currently # 0701775.  ... 
doi:10.1561/0600000021 fatcat:lruiwpvi75bevf5ietum5cn33q

Triple product wavelet integrals for all-frequency relighting

Ren Ng, Ravi Ramamoorthi, Pat Hanrahan
2004 ACM SIGGRAPH 2004 Papers on - SIGGRAPH '04  
We first determine the computational complexity in a number of bases like point samples, spherical harmonics and wavelets.  ...  While image-based and synthetic methods for real-time rendering have been proposed, they do not scale to high sampling rates with variation of both lighting and viewpoint.  ...  Acknowledgments We would especially like to thank Jeff Mancuso for modeling the furniture scene, and Thos. Moser for allowing us to copy the likeness of their Continuous Arm Chair.  ... 
doi:10.1145/1186562.1015749 fatcat:t4dgu5dlznf5xceheswyzw2sci

Triple product wavelet integrals for all-frequency relighting

Ren Ng, Ravi Ramamoorthi, Pat Hanrahan
2004 ACM Transactions on Graphics  
We first determine the computational complexity in a number of bases like point samples, spherical harmonics and wavelets.  ...  While image-based and synthetic methods for real-time rendering have been proposed, they do not scale to high sampling rates with variation of both lighting and viewpoint.  ...  Acknowledgments We would especially like to thank Jeff Mancuso for modeling the furniture scene, and Thos. Moser for allowing us to copy the likeness of their Continuous Arm Chair.  ... 
doi:10.1145/1015706.1015749 fatcat:4a4hd4lylbgiff3liygl4urvpa

Exploiting Temporal Coherence for Incremental All-Frequency Relighting [article]

Ryan Overbeck, Aner Ben-Artzi, Ravi Ramamoorthi, Eitan Grinspun
2006 Symposium on Rendering  
., all-frequency effects are achieved with 30 wavelet coefficients per frame for the lighting, about the same as low-frequency spherical harmonic methods.  ...  Precomputed radiance transfer (PRT) enables all-frequency relighting with complex illumination, materials and shadows.  ...  We thank Ren Ng for making available his code frameworks and scenes for all-frequency relighting.  ... 
doi:10.2312/egwr/egsr06/151-160 fatcat:2apxsxap6bggxm6rvyhhlx3ata

Non-Linear Phase-Shifting of Haar Wavelets for Run-Time All-Frequency Lighting [article]

Mais Alnasser, Hassan Foroosh
2017 arXiv   pre-print
The approach is based on new results derived for non-linear phase shifting in the Haar wavelet domain.  ...  This latter problem arises because the precomputed data are defined in a global coordinate system and encoded in the wavelet domain, while the object is rotated in a local coordinate system.  ...  The latter methods may be dealing with only the relighting problem (image-based relighting) when the viewpoint is assumed stationary but the light changing dynamically, or as a more complex rendering and  ... 
arXiv:1705.07272v1 fatcat:nb2qhtrwk5cuziu43o7odt6wn4

All-Frequency Relighting of Non-Diffuse Objects using Separable BRDF Approximation [article]

Rui Wang, John Tran, David Luebke
2004 Symposium on Rendering  
We then pre-compute light transport matrices corresponding to each BRDF light map, and compress the data with a non-linear wavelet approximation.  ...  Our work extends the wavelet-based approach to relighting of non-diffuse objects.  ...  Acknowledgements The models used are courtesy of the Stanford 3D Scanning Repository. We would like to thank Nolan Goodnight for advice on our work.  ... 
doi:10.2312/egwr/egsr04/345-354 fatcat:ywwmm6h6erfkvjqz5udkw2n4ge

Data-intensive image based relighting

Biswarup Choudhury, Sharat Chandran
2007 Proceedings of the 5th international conference on Computer graphics and interactive techniques in Australia and Southeast Asia - GRAPHITE '07  
Abstract Image based Relighting(IBRL) has attracted a lot of interest in the computer graphics research, gaming, and virtual cinematography communities for its ability to relight objects or scenes, from  ...  The proposed method thus has lower memory and computational requirements. We demonstrate our results qualitatively and quantitatively with new generated image data.  ...  Special thanks to Deepali Singla for all the help extended during implementations and discussions. We also thank the members of ViGIL, IIT Bombay for their support.  ... 
doi:10.1145/1321261.1321289 dblp:conf/graphite/ChoudhuryC07 fatcat:gb6lpeyapjgd5nuk6x6mt7stay

Compressive light transport sensing

Pieter Peers, Dhruv K. Mahajan, Bruce Lamond, Abhijeet Ghosh, Wojciech Matusik, Ravi Ramamoorthi, Paul Debevec
2009 ACM Transactions on Graphics  
In this article we propose a new framework for capturing light transport data of a real scene, based on the recently developed theory of compressive sensing.  ...  Unfortunately, acquiring this image-based data is time and storage intensive.  ...  Nikias for their support and assistance with this work.  ... 
doi:10.1145/1477926.1477929 fatcat:drqfuzzodncvdkgywwyctotopm
« Previous Showing results 1 — 15 out of 144 results