Interactive Ray Tracing for Virtual TV Studio Applications

In the last years, the well known ray tracing algorithm gained new popularity with the introduction of interactive ray tracing methods. The high modularity and the ability to produce highly realistic images make ray tracing an attractive alternative to raster graphics hardware. Interactive ray tracing also proved its potential in the field of Mixed Reality rendering and provides novel methods for seamless integration of real and virtual content. Actor insertion methods, a subdomain of Mixed Reality and closely related to virtual television studio techniques, can use ray tracing for achieving high output quality in conjunction with appropriate visual cues like shadows and reflections at interactive frame rates. In this paper, we show how interactive ray tracing techniques can provide new ways of implementing virtual studio applications.

File Format for Storage of Multimedia Information

AMS Subj. Classification: 68U05, 68P30

Geração de modelos digitais de superfície por meio de plataformas computacionais com estrutura vetorial e raster

Geographic Information Systems (GIS) integrate the technologies related to Geoprocessing, with the ability to manipulate georeferenced information through data storage, management and analysis. One of the GIS applications is the generation of Digital Elevation Models (DEM) as a result of rebuilding the elevation of a region using computation tools and artificial representation. This paper presents the DEM created from a point base in two computational frameworks with different structures (vector and raster), comparing the contour lines generated from these models with the original contour lines from analog cartographic base. It was observed that one of the generated models presented some discrepancies related to real space for both GIS structures. However, using constrained Delaunay's triangulation in raster GIS a digital elevation model was generated with contour lines quite close to the original ones, with satisfactory results. A 3-D terrain representation was also created offering a very useful tool for analysis.

Pesquisa de clip arts combinando imagens raster e vectoriais

Existe actualmente um crescente desenvolvimento de sistemas de armazenamento e pesquisa de imagens. Uma aproximação adoptada nesses sistemas é a recuperação de imagens baseada em conteúdo (CBIR, Content-Based Image Retrieval). No âmbito destas aplicações existem utilizadores que pretendem utilizar imagens clip art para os seus trabalhos e apresentações. Existem muitas imagens clip art espalhadas por diversas bases de dados em sítios na Internet ou em colecções vendidas em dispositivos ópticos. A pesquisa de imagens nestas bases de dados leva os utilizadores a percorrem várias listas de imagens manualmente ou por métodos de pesquisa por texto, muitas vezes ineficientes. Essas bases de dados de clip arts são representadas por imagens vectoriais e imagens raster. Existem várias tecnologias de pesquisa e recuperação de ambos os tipos de imagens clip art, raster e vectoriais, contudo, a investigação tem sido realizada em separado sem retirar partido das duas áreas de investigação em conjunto, no problema de recuperar e explorar colecções de clip arts. O objectivo deste trabalho é implementar um motor de busca para encontrar clip arts em base de dados compostas por imagens vectoriais e imagens raster. O trabalho envolve um conversor de imagens raster em vectoriais, a extracção de características das imagens raster e vectoriais e a avaliação do sistema de recuperação de clip arts.

Frame-coherent 3D stippling for non-photorealistic computer graphics

Stipping, non-photorealistic rendering, non-photorealistic computer graphics

Embedding metadata in computer graphics for interaction

Illustration Watermarks, Image annotation, Virtual data exploration, Interaction techniques

Dynamic graphics of parametrically linked multivariate methods used in compositional data analysis

Many multivariate methods that are apparently distinct can be linked by introducing oneor more parameters in their definition. Methods that can be linked in this way arecorrespondence analysis, unweighted or weighted logratio analysis (the latter alsoknown as "spectral mapping"), nonsymmetric correspondence analysis, principalcomponent analysis (with and without logarithmic transformation of the data) andmultidimensional scaling. In this presentation I will show how several of thesemethods, which are frequently used in compositional data analysis, may be linkedthrough parametrizations such as power transformations, linear transformations andconvex linear combinations. Since the methods of interest here all lead to visual mapsof data, a "movie" can be made where where the linking parameter is allowed to vary insmall steps: the results are recalculated "frame by frame" and one can see the smoothchange from one method to another. Several of these "movies" will be shown, giving adeeper insight into the similarities and differences between these methods

Dynamic graphics of parametrically linked multivariate methods used in compositional data analysis

Many multivariate methods that are apparently distinct can be linked by introducing oneor more parameters in their definition. Methods that can be linked in this way arecorrespondence analysis, unweighted or weighted logratio analysis (the latter alsoknown as "spectral mapping"), nonsymmetric correspondence analysis, principalcomponent analysis (with and without logarithmic transformation of the data) andmultidimensional scaling. In this presentation I will show how several of thesemethods, which are frequently used in compositional data analysis, may be linkedthrough parametrizations such as power transformations, linear transformations andconvex linear combinations. Since the methods of interest here all lead to visual mapsof data, a "movie" can be made where where the linking parameter is allowed to vary insmall steps: the results are recalculated "frame by frame" and one can see the smoothchange from one method to another. Several of these "movies" will be shown, giving adeeper insight into the similarities and differences between these methods.

Generating a raster map presentation of a forest resource by solving a transportation problem

Abstract

Developing raster bands computed from LiDAR to improve forest

This study examines the use of di erent features derived from remotely sensed data in segmentation of forest stands. Surface interpolation methods were applied to LiDAR points in order to represent data in the form of grayscale images. Median and mean shift ltering was applied to the data for noise reduction. The ability of di erent compositions of rasters obtained from LiDAR data and an aerial image to maximize stand homogeneity in the segmentation was evaluated. The quality of forest stand delineations was assessed by the Akaike information criterion. The research was performed in co-operation with Arbonaut Ltd., Joensuu, Finland.

Open source solutions for multiplatform graphics programming

New emerging technologies in the recent decade have brought new options to cross platform computer graphics development. This master thesis took a look for cross platform 3D graphics development possibilities. All platform dependent and non real time solutions were excluded. WebGL and two different OpenGL based solutions were assessed via demo application by using most recent development tools. In the results pros and cons of the each solutions were noted.

Graphics for engineers, architects, and builders : a manual for designers, an a text - book for scientific schools. Trusses and arches analyzed and discussed by graphical methods

UANL