information

contact

Mark Colbert, Ph.D.
e-mail: mark.c.colbert@gmail.com
former (but still great) advisers: Charles E. Hughes and Erik Reinhard
former labs: Media Convergence Lab and UCF Graphics Group
IMDB
LinkedIn

Currently, I am working as a Software Engineer over at Google.

publications

Mark Colbert. Appearance-driven Material Design, Ph.D. Dissertation, University of Central Florida, August 2008.
PDF

Mark Colbert and Jaroslav Křivánek. Real-time Dynamic Shadows for Image-Based Lighting, Section 4.3, ShaderX 7 - Advanced Rendering Techniques.

Jaroslav Křivánek and Mark Colbert. Real-time Shading with Filtered Importance Sampling, Computer Graphics Forum (Proc. of Eurographics Symposium on Rendering), Vol. 27, No. 4, 2008.
PDF | Video | Slides

Mark Colbert and Jaroslav Křivánek. Real-time Shading with Filtered Importance Sampling, SIGGRAPH 2007 Sketch.
Video | Slides

Mark Colbert and Jaroslav Křivánek. GPU-based Importance Sampling, Chapter 20, GPU Gems 3.

Mark Colbert, Erik Reinhard, and Charles E. Hughes, 'Painting in High Dynamic Range,' Elsevier Journal of Visual Communication and Image Representation, Vol. 18, No. 5, 2007.
PDF Note the link is to the full color technical report

Mark Colbert, Sumanta Pattanaik, Jaroslav Křivánek, 'BRDF-Shop: Creating Physically Correct Bidirectional Reflectance Distribution Functions,' IEEE Computer Graphics and Applications, Vol. 26, No. 1, January/February 2006.
PDF | BibTeX

Erik Reinhard, Ahmet Oguz Akuyz, Mark Colbert, Charles E Hughes and Matthew O'Connor, 'Real-time color blending of rendered and captured video', Interservice/Industry Training, Simulation and Education Conference, December 2004.

project pages

Interactive Material Design via Neuroevolution

Neuroevolution-based interactive optimization algorithm for designing spatially-varying material functions using brush strokes under complex environment lighting.

Real-time Shading with Filtered Importance Sampling

Single GPU shader algorithm for real-time glossy surface reflection using filtered importance sampling.

Painting in High Dynamic Range

A novel approach for painting with constrasts greater than the luminance range of a commodity display.

BRDF-Shop

BRDF-Shop is a novel user interface that allows artists to design materials by painting highlights onto a spherical canvas.

reports

Mark Colbert, Erik Reinhard, and Charles E. Hughes, 'Painting in High Dynamic Range,' Technical Report CS-TR-06-11, November 2006.
PDF

unpublished fun

GPU-based Arbitrarily Sparse Matrix Vector Multiplication

In this project, we propose three novel approaches to performing vector multiplication on arbitrarily sparse matrices. We developed the proposed methods specifically for implementation on the Graphics Processing Unit with an emphasis on increasing speed for very large sparse matrices. The novel method, Boxed-TJDS, Boxed-CRS and Hybrid Boxed-TJDS, were designed using the preexisting sparse matrix storage formats CRS and TJDS. We perform an empirical analysis of the the novel approaches against an SSE implementation of the mathematical operation using matrices of varying sparsity and size. Our results show that the three novel methods represent a range of possibilities for sparse matrix vector multiplication. While the Hybrid and Boxed-TJDS methods perform moderately slower than and comparable to the SSE implementation, respectively, the Boxed-CRS approaches performs considerably faster than SSE as the matrix size increases in non-zero values.

Adaptive Block-based Image Coding with Pre-/post-filtering

We present a tutorial on adaptive, or variable, block sizes with both pre- and post-filtering for improved lossy image compression. We explain the inherit benefits of adaptive block size encoding in comparison to the JPEG and JPEG2000 standard. Additionally, we look at the possibility of using perceptually based importance operators, used in High Dynamic Range imaging and importance sampling, as a method for determining block size. Finally, we implement and compare different adaptive block size techniques after DCT, quantization, arithmetic encoding.

Shadow Mapping Optimization

In this article, we formulate the optimization problem for shadow maps without providing any good answer to the problem. For our purpose, a shadow map is a rasterized image ofdepth information for a scene from a light's perspective. The map is used in rendering to test if a given pixel is visible with respect to a light source.

goodies

Maya-PBRT

The Maya-PBRT project provides users of the PBRT renderer an easy method for designing and developing scenes in Alias's Maya. The project gives the opportunity for researchers to produce complicated scenes without writing intricate input files. At the same time, the project provides artists a rendering utility for physically-based rendering.

PBRT Goodies

PBRT plug-ins I have made throughout the scope of working on different research projects, including a Wavefront OBJ parser and a Targa Film plugin.

Spherical Harmonics Demo (Windows)

A demo providing plots for the different spherical harmonic bands and interactive manipulation of the Spherical Harmonic lighting coefficients. Additionally, a demo of environment lighting is provided with multiple environments, courtesy of Paul Debevec, under two different meshes.

Multiple Render Targets (FBOs) in OpenGL (Code)

Sample code for creating an application in OpenGL that renders out to 4 textures simultaneously.

VS.NET 2005 OpenGL Application Wizard

If you have VS.NET 2005, install this little widget, by running the install batch file, and it will let you quickly create OpenGL applications. It works by giving you an option in VS.NET 2005 for an OpenGL Visual C++ project, choose it, follow the wizard, and you will have a complete OpenGL program which compiles and is ready to go.  The wizard provides functionality for choosing the enabled callbacks, graphical context, and the ability to enable the Cg framework. The only caveat is that it assumes all the external include directories and library paths are set within VS.NET.

courses

MCL GPU Ramp-Up Seminar Series (Spring '08) - Instructor for modern GPU-based rendering algorithms.
FIEA Graphics Course (Summer '07) - Instructor for fundamental graphics and GPU algorithms.
COT5310 (Fall '06) - Teaching Assistant for computability and recursive function theory course.
GPU Programming Seminar Series (Summer '06) - Lecturer/Organizer
CAP 4720 (Fall '05) - Co-Instructor teaching the GPU-pipeline and programmable GPU-based algorithms.
CAP 5725 (Spring '05) - Teaching Assistant creating educational graphics framework software for students.

reviewer

SIGGRAPH 2010 - Reviewer
SIGGRAPH Asia 2009 - Sketches & Posters Committee Member
Eurographics 2009 - Reviewer
SIGGRAPH 2008 - Reviewer
EGSR 2008 - Reviewer
Eurographics 2008 - Reviewer