DOCSLIB.ORG

Multi-View Image Fusion

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Multi-View Image Fusion Multi-view Image Fusion Marc Comino Trinidad1 Ricardo Martin Brualla2 Florian Kainz2 Janne Kontkanen2 1Polytechnic University of Catalonia, 2Google Inputs Outputs Color Transfer Mono Color High-def mono Color High-def color HDR Fusion Color EV+2 Color EV-1 Color EV+2 Color EV-1 Denoised Detail Transfer DSLR Stereo DSLR Low-def stereo High-def stereo Figure 1: We present a method for multi-view image fusion that is a applicable to a variety of scenarios: a higher resolution monochrome image is colorized with a second color image (top row), two color images with different exposures are fused into an HDR lower-noise image (middle row), and a high quality DSLR image is warped to the lower quality stereo views captured by a VR-camera (bottom row). Abstract 1. Introduction In this paper we focus on the problem of fusing multiple We present an end-to-end learned system for fusing mul- misaligned photographs into a chosen target view. Multi- tiple misaligned photographs of the same scene into a cho- view image fusion has become increasingly relevant with sen target view. We demonstrate three use cases: 1) color the recent influx of multi-camera mobile devices. transfer for inferring color for a monochrome view, 2) HDR The form factor of these devices constrains the size of fusion for merging misaligned bracketed exposures, and 3) lenses and sensors, and this limits their light capturing abil- detail transfer for reprojecting a high definition image to ity. Cameras with larger lens apertures and larger pixels the point of view of an affordable VR180-camera. While the capture more photons per pixel, and thus show less promi- system can be trained end-to-end, it consists of three dis- nent photon shot noise. This is the reason mobile cameras tinct steps: feature extraction, image warping and fusion. have been lagging behind large DSLR systems in quality. We present a novel cascaded feature extraction method that In recent years the use of computational photography has enables us to synergetically learn optical flow at different narrowed the gap significantly [11, 17, 19], but the funda- resolution levels. We show that this significantly improves mentals have not changed: more light means better images. the network’s ability to learn large disparities. Finally, we Lately it has become common to fit 2, 3 or even 5 cam- demonstrate that our alignment architecture outperforms a eras [1,6] into a single mobile device. The use of multiple state-of-the art optical flow network on the image warping cameras significantly improves the light gathering ability of task when both systems are trained in an identical manner. the device. At the minimum two cameras capture twice the light of a single camera, but often it is possible to do better by recording different aspects of the scene with each camera 1 and then fusing the results to get the best of both worlds. narios: Color transfer, HDR fusion, and Detail transfer. One can envision a number of applications that fall into this class, for example, fusing infrared and color images 2. Related Work [33], HDR fusion using bracketed exposures [28], or fusing 2.1. High-Dynamic Range Imaging wide-angle and telephoto views for super-resolution within The seminal work of Devebec and Malik [14] presented the central region of the wide-angle image. In this paper a model of a camera’s pixel response that allows fusing mul- we show an end-to-end learned system that is suitable for a tiple exposures into an HDR image. Although they assumed number of multi-view fusion applications. We demonstrate a static camera and scene, the technique has recently been its effectiveness in three compelling multi-camera designs: introduced to mobile cameras, where a stack of frames is Color transfer: Monochrome cameras, such as those fused to generate an HDR-composite [11, 17, 19]. This available in some smart phones [1,3] capture roughly three works the best if the misalignment between the frames is times the number of photons compared to the cameras with moderate, which is not the case in some of our applications color mosaic sensors and do not exhibit artifacts introduced (we show this in the supplementary material). by the mosaic. We explore fusing together a color image Kalantari and Ramamoorthi [23] use a neural network and monochrome image from slightly different view points to generate HDR images from exposure stacks of dynamic to combine the desirable aspects of both cameras. scenes and corresponding precomputed flow fields. Wu et HDR fusion: We explore an HDR camera design where al [35] propose a similar technique that does not require two cameras take photographs simultaneously but with dif- computing optical flow. Others have focused on burst im- ferent exposure settings. We show that fusing the images age fusion by using either recurrent networks [18] or per- reduces noise and increases the dynamic range. mutation invariant networks [8]. In contrast, our proposed Detail transfer: We explore a novel architecture for method jointly estimates a warp and fuses the different im- building a high-quality VR180[2] camera, where a high- ages to generate a high-quality composite. resolution image taken by a DSLR camera is warped to the points of view of a cheaper VR180 camera with a field of 2.2. Image Colorization view close to 180 degrees and a lens separation that matches There is a large amount of literature on single image col- the human interpupillary distance (IPD). The sizes of the orization [21, 37]. Most of the methods presented attempt to the lenses and bodies of DSLR cameras make it difficult to generate artificial but plausible colors for grayscale images. record VR180 with a pair of DSLRs and achieve a small Jeon et al. [22] study stereo matching between a color enough IPD; our design sidesteps this issue. and a monochrome image in order to compute pixel dispar- Our system can be trained end-to-end but it consists of ity. They convert the monochrome image to YUV (lumi- three conceptual stages: feature extraction, warping and fu- nance/chroma) format and populate the chroma (U and V) sion. We use a novel cascaded feature pyramid that en- channels with information from the color input, using the ables synergetic learning of image alignment across differ- previously computed disparity. ent scales. We show that this architecture has a dramatic Wang et al. [33] propose colorizing infrared and ultravio- impact on learning alignment over large disparities. Instead let flash images in order to obtain low-noise pictures in low- of training the network to predict optical flow and using that light conditions. However, their alignment is based on opti- for alignment, we employ the idea of task oriented flow [36] cal flow [9], and their neural network also needs to learn to to optimize directly for our use cases since this has proven account for misregistration artifacts, whereas our network to produce better results. aligns and colorizes at the same time. We demonstrate the performance of our system with an ablation study and compare it with a state of the art optical 2.3. VR Imaging flow network [32]. We also compare our HDR fusion tech- For virtual reality applications one would ideally cap- nique against Kalantari et al. [23], obtaining comparable re- ture a complete light field video of a scene. Multiple cam- sults. Finally, we provide a large number of high resolution era designs have been proposed towards this end, includ- examples in the supplementary material. ing rings [9] or spheres [26] of outward-facing cameras, or To summarize, the main contributions of this work are: planar camera arrays [34]. Many of these systems do not 1) A novel end-to-end CNN architecture for merging in- directly produce stereo views that match the human inter- formation from multiple misaligned images. 2) An image pupillary distance, but rely on view interpolation to gener- warping module that employs a cascaded feature pyramid ate novel views of the scene using computational methods. to learn optical flow on multiple resolution levels simultane- Using our proposed method for multi-lens fusion, we en- ously. We show that this produces better results than state- vision creating a VR camera where we use detail transfer to of-the-art optical flow for multi-view fusion. 3) A demon- project a high quality DSLR image into the viewpoints of stration of the proposed architecture in three different sce- a VR camera that captures images with the baseline that 2 inputs Feature Extraction Warping Fusion t0 t0 A0 s0 w(s0) Flow F Module + 0 t1 t1 H x W x 3 A0 A1 s1 w(s1) fused output Flow F + Module + 1 image pyramid A0 A1 A2 t2 t2 dataflow s2 w(s2) 2x2 avg. pooling Flow F + + Module + 2 2x resize feature concatenation ··· + ··· ··· ··· ··· ··· ··· features kernels Figure 2: Our architecture takes inspiration from U-Net [30] with an encoder (feature extraction, Section 3.1) on the left and a decoder (fusion, Section 3.3) on the right. Since U-Net cannot efficiently align images, an additional warping module is inserted in the middle (Section 3.2). The green blocks An and Fk are kernels whereas the blue blocks represent features. Blocks An for n = 0; 1; 2 are feature extraction kernels that are sequentially applied to each level of the image pyramid. For each level k, we concatenate the features obtained by applying A0 on the current level, A1 on the previous level and A2 on the level before the previous one, yielding features sk for the source 4 5 6 image and tk for the target.
Load more

Recommended publications
  • Bibliography.Pdf
    Bibliography Thomas Annen, Jan Kautz, Frédo Durand, and Hans-Peter Seidel. Spherical harmonic gradients for mid-range illumination. In Alexander Keller and Henrik Wann Jensen, editors, Eurographics Symposium on Rendering, pages 331–336, Norrköping, Sweden, 2004. Eurographics Association. ISBN 3-905673-12-6. 35,72 Arthur Appel. Some techniques for shading machine renderings of solids. In AFIPS 1968 Spring Joint Computer Conference, volume 32, pages 37–45, 1968. 20 Okan Arikan, David A. Forsyth, and James F. O’Brien. Fast and detailed approximate global illumination by irradiance decomposition. In ACM Transactions on Graphics (Proceedings of SIGGRAPH 2005), pages 1108–1114. ACM Press, July 2005. doi: 10.1145/1073204.1073319. URL http://doi.acm.org/10.1145/1073204.1073319. 47, 48, 52 James Arvo. The irradiance jacobian for partially occluded polyhedral sources. In Computer Graphics (Proceedings of SIGGRAPH 94), pages 343–350. ACM Press, 1994. ISBN 0-89791-667-0. doi: 10.1145/192161.192250. URL http://dx.doi.org/10.1145/192161.192250. 72, 102 Neeta Bhate. Application of rapid hierarchical radiosity to participating media. In Proceedings of ATARV-93: Advanced Techniques in Animation, Rendering, and Visualization, pages 43–53, Ankara, Turkey, July 1993. Bilkent University. 69 Neeta Bhate and A. Tokuta. Photorealistic volume rendering of media with directional scattering. In Alan Chalmers, Derek Paddon, and François Sillion, editors, Rendering Techniques ’92, Eurographics, pages 227–246. Consolidation Express Bristol, 1992. 69 Miguel A. Blanco, M. Florez, and M. Bermejo. Evaluation of the rotation matrices in the basis of real spherical harmonics. Journal Molecular Structure (Theochem), 419:19–27, December 1997.
    [Show full text]
  • Efficient Ray Tracing of Volume Data
    Efficient Ray Tracing of Volume Data TR88-029 June 1988 Marc Levay The University of North Carolina at Chapel Hill Department of Computer Science CB#3175, Sitterson Hall Chapel Hill, NC 27599-3175 UNC is an Equal Opportunity/ Affirmative Action Institution. 1 Efficient Ray Tracing of Volume Data Marc Levoy June, 1988 Computer Science Department University of North Carolina Chapel Hill, NC 27599 Abstract Volume rendering is a technique for visualizing sampled scalar functions of three spatial dimen­ sions without fitting geometric primitives to the data. Images are generated by computing 2-D pro­ jections of a colored semi-transparent volume, where the color and opacity at each point is derived from the data using local operators. Since all voxels participate in the generation of each image, rendering time grows linearly with the size of the dataset. This paper presents a front-to-back image-order volume rendering algorithm and discusses two methods for improving its performance. The first method employs a pyramid of binary volumes to encode coherence present in the data, and the second method uses an opacity threshold to adaptively terminate ray tracing. These methods exhibit a lower complexity than brute-force algorithms, although the actual time saved depends on the data. Examples from two applications are given: medical imaging and molecular graphics. 1. Introduction The increasing availability of powerful graphics workstations in the scientific and computing communities has catalyzed the development of new methods for visualizing discrete multidimen­ sional data. In this paper, we address the problem of visualizing sampled scalar functions of three spatial dimensions, henceforth referred to as volume data.
    [Show full text]
  • Volume Rendering on Scalable Shared-Memory MIMD Architectures
    Volume Rendering on Scalable Shared-Memory MIMD Architectures Jason Nieh and Marc Levoy Computer Systems Laboratory Stanford University Abstract time. Examples of these optimizations are hierarchical opacity enumeration, early ray termination, and spatially adaptive image Volume rendering is a useful visualization technique for under- sampling [13, 14, 16, 181. Optimized ray tracing is the fastest standing the large amounts of data generated in a variety of scien- known sequential algorithm for volume rendering. Nevertheless, tific disciplines. Routine use of this technique is currently limited the computational requirements of the fastest sequential algorithm by its computational expense. We have designed a parallel volume still preclude real-time volume rendering on the fastest computers rendering algorithm for MIMD architectures based on ray tracing today. and a novel task queue image partitioning technique. The combi- Parallel machines offer the computational power to achieve real- nation of ray tracing and MIMD architectures allows us to employ time volume rendering on usefully large datasets. This paper con- algorithmic optimizations such as hierarchical opacity enumera- siders how parallel computing can be brought to bear in reducing tion, early ray termination, and adaptive image sampling. The use the computation time of volume rendering. We have designed of task queue image partitioning makes these optimizations effi- and implemented an optimized volume ray tracing algorithm that cient in aparallel framework. We have implemented our algorithm employs a novel task queue image partitioning technique on the on the Stanford DASH Multiprocessor, a scalable shared-memory Stanford DASH Multiprocessor [lo], a scalable shared-memory MIMD machine. Its single address-space and coherent caches pro- MIMD (Multiple Instruction, Multiple Data) machine consisting vide programming ease and good performance for our algorithm.
    [Show full text]
  • Computational Photography
    Computational Photography George Legrady © 2020 Experimental Visualization Lab Media Arts & Technology University of California, Santa Barbara Definition of Computational Photography • An R & D development in the mid 2000s • Computational photography refers to digital image-capture cameras where computers are integrated into the image-capture process within the camera • Examples of computational photography results include in-camera computation of digital panoramas,[6] high-dynamic-range images, light- field cameras, and other unconventional optics • Correlating one’s image with others through the internet (Photosynth) • Sensing in other electromagnetic spectrum • 3 Leading labs: Marc Levoy, Stanford (LightField, FrankenCamera, etc.) Ramesh Raskar, Camera Culture, MIT Media Lab Shree Nayar, CV Lab, Columbia University https://en.wikipedia.org/wiki/Computational_photography Definition of Computational Photography Sensor System Opticcs Software Processing Image From Shree K. Nayar, Columbia University From Shree K. Nayar, Columbia University Shree K. Nayar, Director (lab description video) • Computer Vision Laboratory • Lab focuses on vision sensors; physics based models for vision; algorithms for scene interpretation • Digital imaging, machine vision, robotics, human- machine interfaces, computer graphics and displays [URL] From Shree K. Nayar, Columbia University • Refraction (lens / dioptrics) and reflection (mirror / catoptrics) are combined in an optical system, (Used in search lights, headlamps, optical telescopes, microscopes, and telephoto lenses.) • Catadioptric Camera for 360 degree Imaging • Reflector | Recorded Image | Unwrapped [dance video] • 360 degree cameras [Various projects] Marc Levoy, Computer Science Lab, Stanford George Legrady Director, Experimental Visualization Lab Media Arts & Technology University of California, Santa Barbara http://vislab.ucsb.edu http://georgelegrady.com Marc Levoy, Computer Science Lab, Stanford • Light fields were introduced into computer graphics in 1996 by Marc Levoy and Pat Hanrahan.
    [Show full text]
  • Computational Photography Research at Stanford
    Computational photography research at Stanford January 2012 Marc Levoy Computer Science Department Stanford University Outline ! Light field photography ! FCam and the Stanford Frankencamera ! User interfaces for computational photography ! Ongoing projects • FrankenSLR • burst-mode photography • languages and architectures for programmable cameras • computational videography and cinematography • multi-bucket pixels 2 ! Marc Levoy Light field photography using a handheld plenoptic camera Ren Ng, Marc Levoy, Mathieu Brédif, Gene Duval, Mark Horowitz and Pat Hanrahan (Proc. SIGGRAPH 2005 and TR 2005-02) Light field photography [Ng SIGGRAPH 2005] ! Marc Levoy Prototype camera Contax medium format camera Kodak 16-megapixel sensor Adaptive Optics microlens array 125µ square-sided microlenses 4000 ! 4000 pixels ÷ 292 ! 292 lenses = 14 ! 14 pixels per lens Digital refocusing ! ! ! 2010 Marc Levoy Example of digital refocusing ! 2010 Marc Levoy Refocusing portraits ! 2010 Marc Levoy Light field photography (Flash demo) ! 2010 Marc Levoy Commercialization • trades off (excess) spatial resolution for ability to refocus and adjust the perspective • sensor pixels should be made even smaller, subject to the diffraction limit, for example: 36mm ! 24mm ÷ 2.5µ pixels = 266 Mpix 20K ! 13K pixels 4000 ! 2666 pixels ! 20 ! 20 rays per pixel or 2000 ! 1500 pixels ! 3 ! 3 rays per pixel = 27 Mpix ! Marc Levoy Camera 2.0 Marc Levoy Computer Science Department Stanford University The Stanford Frankencameras Frankencamera F2 Nokia N900 “F” ! facilitate research in experimental computational photography ! for students in computational photography courses worldwide ! proving ground for plugins and apps for future cameras 14 ! 2010 Marc Levoy CS 448A - Computational Photography 15 ! 2010 Marc Levoy CS 448 projects M. Culbreth, A. Davis!! ! ! A phone-to-phone 4D light field fax machine J.
    [Show full text]
  • Computational Photography & Cinematography
    Computational photography & cinematography (for a lecture specifically devoted to the Stanford Frankencamera, see http://graphics.stanford.edu/talks/camera20-public-may10-150dpi.pdf) Marc Levoy Computer Science Department Stanford University The future of digital photography ! the megapixel wars are over (and it’s about time) ! computational photography is the next battleground in the camera industry (it’s already starting) 2 ! Marc Levoy Premise: available computing power in cameras is rising faster than megapixels 12 70 9 52.5 6 35 megapixels 3 17.5 billions of pixels / second of pixels billions 0 0 2005 2006 2007 2008 2009 2010 Avg megapixels in new cameras, CAGR = 1.2 NVIDIA GTX texture fill rate, CAGR = 1.8 (CAGR for Moore’s law = 1.5) ! this “headroom” permits more computation per pixel, 3 or more frames per second, or less custom hardware ! Marc Levoy The future of digital photography ! the megapixel wars are over (long overdue) ! computational photography is the next battleground in the camera industry (it’s already starting) ! how will these features appear to consumers? • standard and invisible • standard and visible (and disable-able) • aftermarket plugins and apps for your camera 4 ! Marc Levoy The future of digital photography ! the megapixel wars are over (long overdue) ! computational photography is the next battleground in the camera industry (it’s already starting) ! how will these features appear to consumers? • standard and invisible • standard and visible (and disable-able) • aftermarket plugins and apps for your camera
    [Show full text]
  • Uva-DARE (Digital Academic Repository)
    UvA-DARE (Digital Academic Repository) Interactive Exploration in Virtual Environments Belleman, R.G. Publication date 2003 Link to publication Citation for published version (APA): Belleman, R. G. (2003). Interactive Exploration in Virtual Environments. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:30 Sep 2021 References s [1]] 3rdTech webpage, http://www.3rdtech.com/. [2]] M.J. Ackerman. Accessing the visible human project. D-Lib Magazine: The MagazineMagazine of the Digital Library Forum, October 1995. [3]] H. Afsarmanesh, R.G. Belleman, A.S.Z. Belloum, A. Benabdelkader, J.F.J, vann den Brand, G.B. Eijkel, A. Frenkel, C. Garita, D.L. Groep, R.M.A. Heeren, Z.W.. Hendrikse, L.0. Hertzberger, J.A. Kaandorp, E.C.
    [Show full text]
  • Proposal for a SIGGRAPH 2007 Course
    Proposal for a SIGGRAPH 2008 Course: Computational Photography: Advanced Topics Online ID: courses_0040 1 Course Title Computational Photography 2 Category Image-based and 3D Photography techniques - other 3 Course Organizer Ramesh Raskar MIT-Media Lab (preferred) Mitsubishi Electric Research Labs (MERL) 20 Ames St., 201 Broadway Cambridge, MA 02139, USA Cambridge, MA 02139, USA Jack Tumblin EECS Dept, 3-320 Ford Design Center Northwestern University 2133 Sheridan Road Evanston, IL 60208, USA 4 Proposed Length 3.75 Hour 5 Proposed Presentation Venue Regular session room 6 Summary Statement Participants learn about the latest computational methods in digital imaging that overcome the traditional limitations of a camera and enable novel imaging applications. The course provides a practical guide to topics in image capture and manipulation methods for generating compelling pictures for computer graphics and for extracting scene properties for computer vision, with several examples. 7 Names of Lecturers Paul DEBEVEC(University of Southern California, Institute for Creative Technologies (USC-ICT), USA)([email protected]) Ramesh RASKAR (Mitsubishi Electric Research Labs (MERL), USA) ([email protected]) Jack TUMBLIN (Northwestern University, USA) ([email protected]) 8 Course Abstract Abstract Computational photography combines plentiful computing, digital sensors, modern optics, many varieties of actuators, probes and smart lights to escape the limitations of traditional film cameras and enables novel imaging applications. 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, performance capture and interchangeably relighting real and virtual characters are just some of the new applications emerging in Computational Photography.
    [Show full text]
  • Digital Paint Systems: an Anecdotal and Historical Overview
    Digital Paint Systems: An Anecdotal and Historical Overview Alvy Ray Smith The history of digital paint systems derives from many things— chance meetings, coincidences and boredom, artistic license, brilliant researchers, a wealthy benefactor, and, of course, lawsuits. Alvy Ray Smith tells the fascinating story—facts first, then anecdotes—in his own words. This article is based on a talk presented in tal 2D (two-dimensional) and 3D modeling and January 2000 at an evening hosted by the animation, film recording, video editing, and Computer History Museum on Moffatt Field, audio synthesis. An excellent rendering of my near Palo Alto, California. I shared the floor time with Dick Shoup (sounds like “shout,” not with longtime colleague Richard G. “Dick” like “hoop”) in the early days at Xerox PARC Shoup who figures highly in what follows. It is (Palo Alto Research Center) can be found in the also based on a document I submitted to the recent book Dealers of Lightning: Xerox PARC Academy of Motion Picture Arts and Sciences and the Dawn of the Computer Age.4 For other (AMPAS) in 1997 in answer to a call from them PARC references, see Lavendel,5 Pake,6 Perry,7 for information about early paint programs and and Smith.8 their contribution to the film business.1 The time frame dates from the late 1960s to Definitions the early 1980s, from the beginnings of the A digital paint program and a digital paint technology of digital painting up to the first system are distinguished by their functions. A consumer products that implemented it.
    [Show full text]
  • Acquisition and Representation of Material Appearance for Editing
    Acquisition and Representation of Material Appearance for Editing and Rendering Jason Davis Lawrence A Dissertation Presented to the Faculty of Princeton University in Candidacy for the Degree of Doctor of Philosophy Recommended for Acceptance By the Department of Computer Science September 2006 c Copyright by Jason Davis Lawrence, 2006. All rights reserved. Abstract Providing computer models that accurately characterize the appearance of a wide class of materials is of great interest to both the computer graphics and computer vision communities. The last ten years has witnessed a surge in techniques for measuring the optical properties of physical materials. As compared to conventional techniques that rely on hand-tuning parametric light reflectance functions, a data-driven approach is better suited for representing complex real-world appearance. However, incorporating these representations into existing rendering algorithms and a practical production pipeline has remained an open research problem. One common approach has been to fit the parameters of an analytic reflectance function to measured appearance data. This has the benefit of providing significant compression ratios and these analytic models are already fully integrated into modern rendering algorithms. However, this approach can lead to significant approximation errors for many materials and it requires computationally expensive and numerically unstable non-linear optimization. An alternative approach is to compress these datasets, using algorithms such as Principal Component Analysis, wavelet compression or matrix factorization. Although these techniques provide an accurate and compact representation, they do have several drawbacks. In particular, existing methods do not enable efficient importance sampling for measured materials (and even some complex analytic models) in the context of physically-based rendering systems.
    [Show full text]
  • Handheld Multi-Frame Super-Resolution
    Handheld Multi-Frame Super-Resolution BARTLOMIEJ WRONSKI, IGNACIO GARCIA-DORADO, MANFRED ERNST, DAMIEN KELLY, MICHAEL KRAININ, CHIA-KAI LIANG, MARC LEVOY, and PEYMAN MILANFAR, Google Research Fig. 1. We present a multi-frame super-resolution algorithm that supplants the need for demosaicing in a camera pipeline by merging a burst of raw images. We show a comparison to a method that merges frames containing the same-color channels together first, and is then followed by demosaicing (top). By contrast, our method (bottom) creates the full RGB directly from a burst of raw images. This burst was captured with a hand-held mobile phone and processed on device. Note in the third (red) inset that the demosaiced result exhibits aliasing (Moiré), while our result takes advantage of this aliasing, which changes on every frame in the burst, to produce a merged result in which the aliasing is gone but the cloth texture becomes visible. Compared to DSLR cameras, smartphone cameras have smaller sensors, CCS Concepts: • Computing methodologies → Computational pho- which limits their spatial resolution; smaller apertures, which limits their tography; Image processing. light gathering ability; and smaller pixels, which reduces their signal-to- Additional Key Words and Phrases: computational photography, super- noise ratio. The use of color filter arrays (CFAs) requires demosaicing, which further degrades resolution. In this paper, we supplant the use of traditional resolution, image processing, photography demosaicing in single-frame and burst photography pipelines with a multi- ACM Reference Format: frame super-resolution algorithm that creates a complete RGB image directly Bartlomiej Wronski, Ignacio Garcia-Dorado, Manfred Ernst, Damien Kelly, from a burst of CFA raw images.
    [Show full text]
  • Proceedings August 3-8, 1997 Papers Chair: Turner Whitted Panels Chair: Barbara Mones-Hattal
    Annual Conference Series 1997 SIGGRAPH 97 Conference Proceedings August 3-8, 1997 Papers Chair: Turner Whitted Panels Chair: Barbara Mones-Hattal A Publication of ACM SIGGRAPH Sponsored by the ACM's Special Interest Group on Computer Graphics PROCEEDINGS COMPUTER GRAPHICS Proceedings, Annual Conference Series, 1997 Contents Papers Preface 8 Panels Preface 9 Papers Sessions, Wednesday, 6 August 8:15 - 9:45 SIGGRAPH 97 Keynote Address Steven A. Coons Award for Outstanding Creative Contributions to Computer Graphics 10 1997 ACM SIGGRAPH Computer Graphics Achievement Award 11 10:15 - 12:00 Virtual Reality and Applications Chair: Frederick P. Brooks, Jr. Quantifying Immersion in Virtual Reality 13 Randy Pausen, Dennis Proffitt, George Williams Moving Objects in Space: Exploiting Proprioception In Virtual-Environment Interaction 19 Mark R. Mine, Frederick P. Brooks, Jr, Carlo H. Se'quin Virtual Voyage: Interactive Navigation in the Human Colon 27 Lichan Hong, Shigeru Muraki, Arie Kaufman, Dirk Bartz, Taosong He Interactive Simulation of Fire in Virtual Building Environments 35 Richard Bukowski, Carlo H. Sequin 2:00 - 3:45 Illumination Chair: Eugene Fiume Fitting Virtual Lights For Non-Diffuse Walkthroughs 45 Bruce Walter, Gün Alppay, Eric P. F. Lafortune, Sebastian Femandez, Donald P. Greenberg Instant Radiosity 49 Alexander Keller Interactive Update of Global Illumination Using A Line-Space Hierarchy 57 George Drettakis, Francois Sillion Metropolis Light Transport 65 Eric Veach, Leonidas J. Guibas 4:00 - 5:45 Visibility Chair: Thomas Funkhouser Visibility Culling Using Hierarchical Occlusion Maps 77 Hansong Zhang, Dinesh Manocha, Thomas Hudson, Kenneth E. Hoff III The Visibility Skeleton: A Powerful and Efficient Multi-Purpose Global Visibility Tool 89 Fredo Durand, George Drettakis, Claude Puech Rendering Complex Scenes with Memory-Coherent Ray Tracing 101 Matt Pharr, Craig Kolb, Reid Gershbein, Pat Hanrahan Illustrating Surface Shape in Volume Data via Principal Direction-Driven 3D Line Integral Convolution 109 Victoria L.
    [Show full text]