Reynold Bailey - Publications [Switch to Concise View] [Home]

 
Relevant Real-World Undergraduate Research Problems: Lessons from the NSF-REU Trenches
Reynold Bailey (Moderator), Guy-Alain Amoussou, Tiffany Barnes, Hans-Peter Bischof, and Thomas Naps, Proceedings of the 41st ACM Technical Symposium on Computer Science Education SIGCSE 2010.
[PDF]
 
Abstract:
   
  Projects funded by the National Science Foundation (NSF) Research Experiences for Undergraduates (REU) program aim to (a) enhance participation of students who otherwise might not have research opportunities, and (b) increase the number of students interested in graduate programs, thus expanding the pool of a well-trained scienti c workforce. To provide meaningful experiences for these students, REU projects make use of a set of interesting, appropriate re- search problems that can be tackled in 8 to 10 weeks in summer.

The panelists have all served as PIs or Co-PIs on NSF REU projects in computing. They will present their REU research problems, highlight challenges they encountered, and present their results. They will also discuss what they have done, or what can be done, to incorporate such research problems within the regular computing curriculum, for ex- ample, in capstone courses or senior projects. A signi cant amount of time will be set aside for audience participation and discussion.

 
 
RenderMan's Power to Visualization's Rescue (NSF-REU student paper)
Julio Espinal, Virginia Allen, Kwesi Amable, Reynold Bailey, and Hans-Peter Bischof, 18th International Conference on Computer Graphics, Visualization and Computer Vision, 2010.
[PDF]
 
Abstract:
   
  Most visualization systems employ a data flow approach in order to create visual representations of data. The data flows along a directed graph through the different components, gets filtered, extracted, analyzed, and finally converted into an image. Most visualization systems use one graphic toolkit or library to create the image. These toolkits and libraries are not created equally; some are better suited than others to solve given problems. Being able to pick and choose would often generate a better result. Within the Spiegel framework any toolkit, which can be used in a Java environment, can be employed to create the image. In this paper, we explain the Spiegel framework and how Pixar's PhotoRealistic RenderMan® can be used to visualize scientific data.
 
 
Search Task Performance Using Subtle Gaze Direction with the Presence of Distractors
 
Ann McNamara, Reynold Bailey, and Cindy Grimm, ACM Transactions on Applied Perception, Vol. 6, No. 3, 2009.
[PDF]
 
Abstract:
   
  A new experiment is presented which demonstrates the usefulness of an image space modulation technique called Subtle Gaze Direction (SGD) for guiding the user in a simple searching task. SGD uses image space modulations in the luminance channel to guide a viewer’s gaze about a scene without interrupting their visual experience. The goal of SGD is to direct a viewer’s gaze to certain regions of a scene without introducing noticeable changes in the image. Using a simple searching task we compared performance using no modulation, using subtle modulation and using obvious modulation. Results from the experiments show improved performance when using subtle gaze direction, without affecting the user’s perception of the image. We then extend the experiment to evaluate performance with the presence of distractors. The distractors took the form of extra modulations which do not correspond to a target in the image. Experimentation shows, that, even in the presence of distractors, more accurate results are returned on a simple search task using SGD, as compared to results returned when no modulation at all is used. Results establish the potential of the method for a wide range of applications including gaming, perceptually based rendering, navigation in virtual environments and medical search tasks.
 
 
 Improving Search Task Performance Using Subtle Gaze Direction
 
Ann McNamara, Reynold Bailey, and Cindy Grimm, APGV ’08: Proceedings of the 5th Symposium on Applied Perception in Graphics and Visualization, 2008.
[PDF]
 
Abstract:
   
  A new experiment is presented which demonstrates the usefulness of an image space modulation technique called Subtle Gaze Direction (SGD) for guiding the user in a simple searching task. SGD uses image space modulations in the luminance channel to guide a viewer’s gaze about a scene without interrupting their visual experience. The goal of SGD is to direct a viewer’s gaze to certain regions of a scene without introducing noticeable changes in the image. Using a simple searching task we compared performance using no modulation, using subtle modulation and using obvious modulation. Results from the experiments show improved performance when using subtle gaze direction, without affecting the user’s perception of the image. Results establish the potential of the method for a wide range of applications including gaming, perceptually based rendering, navigation in virtual environments and medical search tasks.
 
 
Subtle Gaze Direction
 
Reynold Bailey, Ann McNamara, Nisha Sudarsanam, and Cindy Grimm, ACM Transactions on Graphics (TOG), 2009, Vol. 28, No. 4, 2009.
[PDF]
 
Abstract:
   
  This paper presents a novel technique that combines eye-tracking with subtle image-space modulation to direct a viewer's gaze about a digital image. We call this paradigm subtle gaze direction. Subtle gaze direction exploits the fact that our peripheral vision has very poor acuity compared to our foveal vision. By presenting brief, subtle modulations to the peripheral regions of the field of view, the technique presented here draws the viewer's foveal vision to the modulated region. Additionally, by monitoring saccadic velocity and exploiting the visual phenomenon of saccadic masking, modulation is automatically terminated before the viewer's foveal vision enters the modulated region. Hence, the viewer is never actually allowed to scrutinize the stimuli that attracted her gaze. This new subtle gaze directing technique has potential application in many areas including large scale display systems, perceptually adaptive rendering, and complex visual search tasks.
 
 
Perception-Guided Image Manipulation
 
Reynold Bailey, Ph.D. Dissertation, Department of Computer Science and Engineering, Washington University in St. Louis, 2007
Date of Defense: July 13, 2007
[PDF] [Dissertation Defense Slides]
 
Abstract:
   
  This dissertation presents a novel approach to image editing and manipulation where the goal is to explicitly trigger certain visual cues. We refer to this as perceptually meaningful image manipulation. Existing image editing approaches typically do not take human visual perception into account, whereas our approach relies heavily on the principles of human visual perception. We present computer-based techniques for simulating artistic control of apparent depth in an image, conveying a sense of motion in an image, and subtly directing a viewer's gaze about an image. Our techniques combine elements of traditional art with research from various fields of science.

Our image-based technique for simulating artistic control of apparent depth works by automatically adjusting color or luminance in specific regions of an image. The color and luminance adjustment is based on several simple rules that artists use to convey and manipulate apparent depth in their work. Our technique for conveying a sense of motion in a visually static image introduces spatial imprecision in the image plane. This is also patterned after work done by traditional artists. It has been suggested that spatially imprecise stimuli are processed differently by our foveal vision and our peripheral vision and that this difference in visual processing causes the image to appear to have a dynamic component. Finally, our subtle gaze directing technique exploits differences in visual acuity and processing speed between our foveal and peripheral vision. We present brief, subtle image-space modulations to the low acuity peripheral regions of the field of view. These stimuli, which are detected quickly, attract the slower, high acuity foveal vision to fixate on the modulated regions.
 
 
Perceptually Meaningful Image Editing: Manipulating Perceived Depth and Creating the Illusion of Motion in 2D Images
 
Reynold Bailey and Cindy Grimm, The Visual Computer, Vol. 23, No. 9-11, September 2007.
[PDF]
 
Abstract:
   
  We introduce a novel concept called perceptually meaningful image editing and present techniques for manipulating the apparent depth of objects and creating the illusion of motion in 2D images. Our techniques combine principles of human visual perception with approaches developed by traditional artists. For our depth manipulation technique, the user loads an image, selects an object and specifies whether the object should appear closer or further away. The system automatically determines luminance or color temperature target values for the object and/or background that achieve the desired depth change. Our approach for creating the illusion of motion exploits the differences between our peripheral vision and our foveal vision by introducing spatial imprecision to the image.
 
 
The Effect of Object Color on Depth Ordering
 
Reynold Bailey, Cindy Grimm, Christopher Davoli, and Richard Abrams, Technical Report 2007-18, Washington University in St. Louis, 2007.
[PDF]
 
Abstract:
 
 

The relationship between color and perceived depth for realistic, colored objects with varying shading was explored. Background: Studies have shown that warm-colored stimuli tend to appear nearer in depth than cool-colored stimuli. The majority of these studies asked human observers to view physically equidistant, colored stimuli and compare them for relative depth. However, in most cases, the stimuli presented were rather simple: straight colored lines, uniform color patches, point light sources, or symmetrical objects with uniform shading. Additionally, the colors were typically highly saturated. Although such stimuli are useful for isolating and studying depth cues in certain contexts, they leave open the question of whether the human visual system operates similarly for realistic objects. Method: Participants were presented with all possible pairs from a set of differently colored objects and were asked to select the object in each pair that appears closest to them. The objects were presented on a standard computer screen, against 4 different uniform backgrounds of varying intensity. Results: Our results show that the relative strength of color as a depth cue increases when the colored stimuli are presented against darker backgrounds and decreases when presented against lighter backgrounds. Conclusion: Color does impact our depth perception even though it is a relatively weak indicator and is not necessarily the overriding depth cue for complex, realistic objects. Application: Our observations can be used to guide the selection of color to enhance the perceived depth of objects presented on traditional display devices and newer immersive virtual environments.

 
 
Table-Top Computed Lighting for Practical Digital Photography
 
Ankit Mohan, Reynold Bailey, Jonathan Waite, Jack Tumblin, Cindy Grimm, and Bobby Bodenheimer, IEEE Transactions on Visualization and Computer Graphics (TVCG), Vol. 13, No. 3, May/June 2007.
[PDF]
Journal version of Eurographics paper
 
Abstract:
   
  We apply simplified image-based lighting methods to reduce the equipment, cost, time, and specialized skills required for high-quality photographic lighting of desktop-sized static objects such as museum artifacts. We place the object and a computer-steered moving-head spotlight inside a simple foam-core enclosure, and use a camera to record photos as the light scans the box interior. Optimization, guided by interactive user sketching, selects a small set of these photos whose weighted sum best matches the user-defined target image. Unlike previous image-based re-lighting efforts, our method requires only one light source, yet can achieve high resolution light positioning to avoid multiple sharp shadows. A reduced version uses only a hand-held light, and may be suitable for battery-powered, field photography equipment that fits into a backpack.
 
 
Non-Photorealistic Rendering 2nd Edition (Book Chapter)
 
Bruce Gooch, Amy Gooch, Mario Costa Sousa (editors), (publication pending).
This book chapter will contain excerpts from my Master's Thesis.
 
 
The Effect of Warm and Cool Object Colors on Depth Ordering
 
Reynold Bailey, Cindy Grimm and Christopher Davoli, In Proceedings of Symposium on Applied Perception in Graphics and Visualization (APGV), Boston, MA, July 2006.
[PDF] [Extended Technical Report] [Poster]
 
Abstract:
   
  Colors that appear closer to the red end of the visible spectrum are said to be warm while the colors that appear closer to the blue end are said to be cool. The phenomenon of warmer colors appearing nearer in depth to viewers than cooler colors has been studied extensively by psychologists and other vision researchers. The vast majority of these studies have asked human observers to view physically equidistant, colored stimuli and compare them for relative depth. However, in most cases, the stimuli presented were rather simple: straight colored lines, uniform color patches, point light sources, or symmetrical objects with uniform shading. Additionally, the colors used were typically highly saturated. Although such stimuli are useful in isolating and studying depth cues in certain contexts, they leave open the question of whether the human visual system operates similarly for realistic objects. This paper presents the results of an experiment designed to explore the color-depth relationship for realistic, colored objects with varying shading and contours.
 
 
The Real Effect of Warm-Cool Colors
 
Reynold Bailey, Cindy Grimm, and Christopher Davoli, Technical Report 2006-17, Washington University in St. Louis, 2006.
[PDF]
Extended version of APGV paper
 
Abstract:
 
 

The phenomenon of warmer colors appearing nearer in depth to viewers than cooler colors has been studied extensively by psychologists and other vision researchers. The vast majority of these studies have asked human observers to view physically equidistant, colored stimuli and compare them for relative depth. However, in most cases, the stimuli presented were rather simple: straight colored lines, uniform color patches, point light sources, or symmetrical objects with uniform shading. Additionally, the colors used were typically highly saturated. Although such stimuli are useful in isolating and studying depth cues in certain contexts, they leave open the question of whether the human visual system operates similarly for realistic objects. This paper presents the results of an experiment designed to explore the color-depth relationship for realistic, colored objects with varying shading and contours.

 
 
Perceptually Meaningful Image Editing: Depth
 
Reynold Bailey and Cindy Grimm, "Perceptually Meaningful Image Editing: Depth", Technical Report 2006-11, Washington University in St. Louis, 2006.
[PDF]
 
Abstract:
 
 

We introduce the concept of perceptually meaningful image editing and present two techniques for manipulating the apparent depth of objects in an image. The user loads an image, selects an object and specifies whether the object should appear closer or further away. The system automatically determines target values for the object and/or background that achieve the desired depth change. These depth editing operations, based on techniques used by traditional artists, manipulate either the luminance or color temperature of different regions of the image. By performing blending in the gradient domain and reconstruction with a Poisson solver, the appearance of false edges is minimized. The results of a preliminary user study, designed to evaluate the effectiveness of these techniques, are also presented.

 
 
Table-Top Computed Lighting for Practical Digital Photography
 
Ankit Mohan, Jack Tumblin, Bobby Bodenheimer, Cindy Grimm, and Reynold Bailey,  In Proceedings of Eurographics Symposium on Rendering (EGSR), Konstanz, Germany, June 2005.
[PDF] [Doctoral Seminar Slides] [Supplemental Results]
 
Abstract:
   
 

We apply simplified image-based lighting methods to reduce the equipment, cost, time, and specialized skills required for high-quality photographic lighting of desktop-sized static objects such as museum artifacts. We place the object and a computer-steered moving-head spotlight inside a simple foam-core enclosure, and use a camera to quickly record low-resolution photos as the light scans the box interior. Optimization guided by interactive user sketching selects a small set of frames whose weighted sum best matches the target image. The system then repeats the lighting used in each of these frames, and constructs a high resolution result from re-photographed basis images. Unlike previous image-based relighting efforts, our method requires only one light source, yet can achieve high resolution light positioning to avoid multiple sharp shadows. A reduced version uses only a hand-held light, and may be suitable for battery-powered, field photography equipment that fits in a backpack.

 
 
Towards a Perception Based Image Editing System
 
Reynold Bailey, Raquel Bujans, and Cindy Grimm, Technical Report 2004-65, Washington University in St. Louis, 2004.
[PDF]
 
Abstract:
 
 

The primary goal of this research is to develop a perception based image editing system. The input to this system will be either a rendered image, a photograph, or a high dynamic range image. We are currently developing techniques that allow the user to edit these images in a perceptually intuitive manner. Specifically we are considering the following image editing features: (1) Warm-cool image adjustment, (2) Intensity adjustment, (3) Contrast adjustment, and (4) Detail adjustment. The algorithms we are developing can be used either in an interactive editing system or for automatic image adjustment.

 
 
A Thesis on Techniques for Non-Photorealistic Shading Using Real Paint
 
Reynold Bailey, Master's Thesis, Department of Computer Science and Engineering, Washington University in St. Louis, 2003
Date of Defense: June 27, 2003
[PDF] [Master's Defense Slides] [Graduate Research Symposium Slides] [Doctoral Seminar Slides]
 
Abstract:
   
  The goal of this research is to explore techniques for shading 3D computer generated models using scanned images of actual paint samples. The techniques presented emphasize artistic control of brush stroke texture and color. We first demonstrate how the texture of a paint sample can be separated from its color transition. Four methods, three real-time and one off-line, for producing rendered images from the paint samples are then presented. Finally, we develop metrics for evaluating how well each method achieves our goal in terms of texture similarity, shading correctness, and temporal coherence.
   
Videos:
 
  Object Based Texture Mapping: [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
 
  Image Based Texture Synthesis:  [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
 
  View Aligned 3D Texture Projection:  [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
 
  View Dependent Interpolation:  [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
 
 
Using Texture Synthesis for Non-Photorealistic Shading from Paint Samples
 
Christopher Kulla, James Tucek, Reynold Bailey, and Cindy Grimm, In Proceedings of the 11th Pacific Conference on Computer Graphics and Applications, Alberta, Canada, October 2003.
[PDF] [Extended Technical Report] [Poster]
 
Abstract:
   
 

This paper presents several methods for shading meshes from scanned paint samples that represent dark to light transitions. Our techniques emphasize artistic control of brush stroke texture and color. We first demonstrate how the texture of the paint sample can be separated from its color gradient. We demonstrate three methods, two real-time and one off-line, for producing rendered, shaded images from the texture samples. All three techniques use texture synthesis to generate additional paint samples. Finally, we develop metrics for evaluating how well each method achieves our goal in terms of texture similarity, shading correctness and temporal coherence.

 
Videos:
     
  Image Based Texture Synthesis:  [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
   
  View Aligned 3D Texture Projection:  [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
   
  View Dependent Interpolation:  [Dark-Red Skull] [Green-Yellow Skull] [Red-Yellow Skull]
 
 
Using Texture Synthesis for Non-Photorealistic Shading from Paint Samples
 
Christopher Kulla, James Tucek, Reynold Bailey, and Cindy Grimm, Technical Report 2003-54, Washington University in St. Louis, 2003.
[PDF]
Extended version of Pacific Graphics paper
 
Abstract:
 
 

This paper presents several methods for shading meshes from scanned paint samples that represent dark to light transitions. Our techniques emphasize artistic control of brush stroke texture and color. We first demonstrate how the texture of the paint sample can be separated from its color gradient. We demonstrate three methods, two real-time and one off-line for producing rendered, shaded images from the texture samples. All three techniques use texture synthesis to generate additional paint samples. Finally, we develop metrics for evaluating how well each method achieves our goal in terms of texture similarity, shading correctness and temporal coherence.

 
 
Theoretical Constraints on Multi-Dimensional Retiming Design Techniques
 
Nelson Passos, Delvin Defoe, Reynold Bailey, Ranette Halverson, and Richard Simpson, In Proceedings of the AeroSense-Aerospace/Defense Sensing, Simulation and Controls, Orlando, FL, April 2001.
[PDF]
 
Abstract:
   
 

Image signal processing depends on computation intensive programs, which include the repetition of sequences of operations coded as nested loops. An effective technique in increasing the computing performance of such applications is the design and use of Application Specific Integrated Circuits using loop transformation techniques, and in particular, multidimensional (MD) retiming. The MD-retiming method improves the instruction-level parallelism of uniform loops. While many have written about the multi-dimensional retiming technique, no results have been published on the possible limitations of its application. This paper presents an analysis of that technique and its constraints when applied to nested loops with known index bounds, such as those found in two and three dimensional image processing.

 
 
A Study of Software Pipelining for Multi-Dimensional Problems
 
Reynold Bailey, Delvin Defoe, Ranette Halverson, Richard Simpson, and Nelson Passos, In Proceedings of 13th International Conference on Parallel and Distributed Computing Systems (PDCS), Las Vegas, NV, August 2000.
[PDF]
 
Abstract:
   
  Computational performance of multi-dimensional applications, such as image processing and fluid dynamics, is highly dependent on the parallelism embedded in nested loops found in the software implementation. Software pipeline techniques for multidimensional applications can be roughly divided into two groups. One focused on optimizing the innermost loop body, while another group attempts to exploit the parallelism across the loop dimensions. This paper presents a comparative study of these two groups of techniques through two methods representative of those classes, Iterative Modulo Scheduling and Push-up Scheduling.