Research


I have a broad research interest that encompasses various aspects of computer graphics and related areas. Nonetheless, the central focus of my work has been the investigation of multiscale models and hierarchical computational methods associated with them.

Below, I summarize my research activity in the following topics:


Download: electronic versions of all papers cited here are available from my Publications page.


Deep Learning

Research in applications of deep learning to Graphics and Image Processing.

Papers:

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Big Data and Visualization

Research in Analysis and Visualization of Large Multimedia Datasets.

Papers and Reports:

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Mixed Reality

Research in new methods for Mixed Reality.

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Moebius Transformations for Omnidirectional Images

Research in applications of Moebius Transformations for 360 panoramic images.

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RGBD and Applications

Research work on RGBD images and applications in the areas of modeling, vision, animation and interfaces.

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GPU Computing

Research on the use of modern GPU architectures for simulation, modeling and visualization.

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Mobile Visual Computing

Investigation of various aspects of Mobile Visual Computing, including: image processing for computational photography and video; interactive graphics and augmented reality

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Augmented Reality

Development of new platforms and software for Augmented Reality.

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3D Stereo

Work on techniques for acquisition and visualization of 3D stereo images and Phantograms.

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Sketch-Based Methods

Research on methods for Sketch-Based Modeling and Rendering.

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Computer Music

Work on several aspects of music synthesis, authoring and interaction.

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RGBN

Research on Modeling and Visualization of Surface Mesostructure using Normal Fields.

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Gigapixel Panoramas

Investigation of Methods and Techniques for Processing and Authoring Gigapixel Panoramic Images.

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Compressive Sensing

Recent research on Compressive Sensing and its applications to Graphics and Vision

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Surface Spectral Analysis

I am researching spectral methods for the analysis of discrete surfaces that are represented by meshes with collaborators from Unicamp.

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Interactive Dance

I am developing a multidisciplinary project for Interactive Digital Art and Contemporary Dance with choreographer Analivia Cordeiro.

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Faces

I am studying different aspects of Facial Modeling and Animation with collaborators from USP and USBC.

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Fluids

I have been applying fluid simulation techniques to create special effects on images.

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Topological Multiresolution

Recent work with my Ph.D. student Esdras Medeiros and collaborators from PUC-Rio investigates topological multiresolution of n-dimensional solid objects.

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Projective Atlas Representation

I am developing a representation for surfaces using projective atlas structure.

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High Dynamic Range Imaging

I have been investigating applications and algorithms for High Dynamic Range Imaging.

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I have also written a book on HDR.

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Fourth Generation Video

My interest in developing advanced vison applications led to the research of a new paradigm for real-time scene capture and analysis.

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3D Photography

Recently, I have conducted research on shape and property acquisition for 3D photography. The main results are on structured ligh coding.

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Texture Synthesis

Since 2001, I have been working on texture synthesis on images and surfaces. This research includes supervision of students from Ecole Polytechnique and collaboration with Microsoft Research China.

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Point-Based Modeling and Rendering

My interest in 3D photography naturally lead to a research on point-based modeling and rendering.

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Subdivision Surfaces

In 2001, I started to do research on subdivision techniques. Some of the results include: a new scheme that generalizes C4 box splines; a semi-regular refinement method for triangulated quadrangulations, and procedural synthesis on subdivision surfaces.

Papers:

Links: (see also links under Hierarchical 4-K Meshes and 4-8 Subdivision )


Hierarchical 4-K Meshes

Hierarchical 4-K Meshes constitue a powerful structure for adaptive variable resolution representation of two dimensional PL manifolds.

I am currently extending this framework to 3D with my former PhD student Vinicius Mello.

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Implicit Surfaces

In 1990, I became interested in implicitly defined surfaces and their applications. Since then, I have done research on modeling, rendering and animation with implicit surfaces. In the area of modeling, I employed multiscale analysis and wavelets for the construction of implicit models, as well as, for the conversion of parametric to implicit representations. In the area of rendering, I have developed techniques for polygonization of implicit surfaces. More recently (1996), I created a method for applying 2D textures onto implicit surfaces. In the area of animation, I have done some work on physical simulation of deformable models.

Papers: (see also papers under surface tesselation and wavelets )

I have also written a book on implicit objects:

Links:


Surface Tesselation

My research on implicit surfaces lead me to study the problem of constructing piecewise linear approximations of surfaces. Initially, I focused on adaptive polygonization of implicit surfaces. Subsequently, I investigated also the tesselation of parametric surfaces. Finally, I developed a unified framework for creating multiresolution meshes from both parametric and implicit surfaces. This work was the basis for surface representation schemes, such as hierarchical triangle strips.

Papers: (see also papers under hierarchical 4-k meshes )

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Applications of Wavelets in Computer Graphics

Since 1994, I have been investigating applications of wavelets in computer graphics. My work in this area includes multiscale implicit models and multiresolution paint systems.

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Image Processing

In the area of image processing, my research activity has been quite diversified. I have worked on image compression, quantization and special effects.

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I have also written a book on Image Processing:

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Halftoning

I have done extensive work on digital halftoning.

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Visorama

I did some work on virtual reality as part of the development of Visorama. This system, among other things, employs image-based rendering techniques for real-time visualization of panoramas.

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Animation

In the area of computer animation, my early work (1989) was on procedural animation systems. More recent work is dedicated to processing of motion capture data, which has also been the subject of a Master's Thesis under my supervision.

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Warping and Morphing

I have done some research in warping and morphing techniques.

I also wrote a book on this subject


Theory of Computer Graphics

My research on theoretical aspects of computer graphics is mainly concerned with the formulation of general mathematical models for graphical objects.

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Human-Computer Interface

In addition to the above topics, I have also done some research in human-computer interfaces.

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A review of my research in Procedural Methods and Multiresolution Models was presented in this invited plenary talk at SIBGRAPI 2002.
[ Slides - PDF format ]


An overview of my academic career from 1976 to 1996 can be found in this Memorial, presented as part of my professorship application at IMPA.
[ Slides - PDF format ]