We present a system called Tuner to systematically analyze the parameter space of complex computer simulations, which are time consuming to run and consequently cannot be exhaustively sampled.
Vismon is designed to support sophisticated data analysis of simulation results by managers who are highly knowledgeable about the fisheries domain but not experts in statistical data analysis. The features of Vismon include sensitivity analysis, comprehensive and global trade-offs analysis, and a staged approach to visualization of the uncertainty of the underlying simulation model.
The body-centered cubic (BCC) lattice is the optimal three-dimensional
sampling lattice. In order to approximate a scalar-valued function
from samples that reside on a BCC lattice, spline-like compact kernels
have been recently proposed. The lattice translates of an admissible
BCC kernel form a shift-invariant approximation space that yields
higher quality approximations as compared to similar spline-like
spaces associated with the ubiquitous Cartesian cubic (CC) lattice.
This thesis introduces a new type of meshes called 5-6-7 meshes. For many mesh processing tasks, low- or high-valence vertices are undesirable. At the same time, it is not always possible to achieve complete vertex valence regularity, i.e., to only have valence-6 vertices. A 5-6-7 mesh is a closed triangle mesh where each vertex has valence 5, 6, or 7. An intriguing question is whether it is always possible to convert an arbitrary mesh into a 5-6-7 mesh.
In this thesis, we address the challenge of computing correspondences between dissimilar shapes. This implies that, although the shapes represent the same class of object, there can be major differences in the geometry, topology, and part composition of the shapes as a whole. Additionally, the dissimilarity can also appear in the form of a shape that possesses additional parts that are not present in another shape. We propose three approaches for handling such shape dissimilarity.
Title: GPU-Based High-Performance Visualization
This talk will give an overview of selected research that we are doing in interactive high-performance visualization at the Geometric Modeling and Scientific Visualization Center at KAUST. Interactive visualization is crucial to exploring, analyzing, and understanding data, such as the data acquired via computed tomography, electron microscopy, or seismic surveys, as well as simulated data, such as the result of fluid simulations. However, the amount of data that is acquired or simulated is increasing rapidly toward the petascale and further, which presents a tremendous challenge to interactive visualization and analysis.
Title: Predicting stereoscopic viewing comfort
Interest in stereoscopic 3D imagery has seen a resurgence in recent years. This development has been primarily driven by the computer gaming and film industries, which are taking advantage of the availability of improved stereoscopic 3D display technology. However, even the latest stereoscopic 3D displays can lead to visual discomfort and fatigue.
Title: Creating High Quality Relightable Buildings from Photographs
The human perceptual system is the key to creating effective and believable 3D imagery from photographs. An otherwise accurate model looks "peculiar" if the surface appears to take on the wrong texture or shininess. A significantly less accurate model with the correct surface appearance on the other hand can appear perfectly plausible. In this talk I will illustrate this idea through example ``hallucinated'' 3D models of textured surfaces and show how such models can be transferred to entire building facades.
Title: Preserving color detail in color projection and visualization: recent developments
Finding correspondences between surfaces is one of the fundamental problems with applications in computer graphics, computer vision, paleontology and molecular biology. We leverage small dimensionality of certain intrinsic transformation spaces to efficiently explore isometric and near-isometric mappings between surfaces.
Title: Geometric Computing for Freeform Architecture
Freeform surfaces play an increasingly important role in contemporary architecture. While digital models are easily created, the actual fabrication and construction of architectural freeform structures remains a challenge. In order to make a freeform design realizable, an optimization process known as rationalization has to be applied.
Geometric silhouettes are arcs on a surface representation that separate front-facing regions from back-facing regions with respect to a given viewpoint. These arcs are in general significantly less complex than the surface itself, and carry a great deal of information describing the surface. In this thesis, we take a plane view of geometric silhouettes, defining them in terms of the tangential planes of the surfaces on which they are defined rather than its local properties. We show that this perspective leads to efficient algorithms as well as a novel characterization of silhouettes based on a silhouette-generating set, or SGS.
Title: Springs Springs Springs and Struts
Consider replacing each edge of a mesh or a graph with either a spring or a strut. Suppose that we then place the vertices of the graph in space such that this physical system is in equilibrium. What does this imply?
Title: Geometry Driven Image Manipulation
Title: Drawing Contour Trees in the Plane
The contour tree compactly describes scalar field topology. From the viewpoint of graph drawing, it is a tree with attributes at vertices and optionally on edges. Standard tree drawing algorithms emphasize structural properties of the tree and neglect the attributes. Applying known techniques to convey this information proves hard and sometimes even impossible. We present several adaptions of popular graph drawing approaches to the problem of contour tree drawing and evaluate them. We identify five aesthetic criteria for drawing contour trees and present a novel algorithm for drawing contour trees in the plane that satisfies four of these criteria. Our implementation is fast and effective for contour tree sizes usually used in interactive systems (around 100 branches) and also produces readable pictures for larger trees, as is shown for a 800 branch example.
Title: Visual Analysis of In-car Communication Networks
Modern cars contain a wide spectrum of functionality, which is implemented by many interconnected electronic control units (ECUs). Overlooking all details of these increasingly complex in-car communication networks is a major challenge for developers. In our work, we have designed a number of analysis tools for in-car communication networks to enable developers to trace errors better and faster. By observing current working practices of automotive analysis experts, we found that the tools in use are mostly text-based and often fail to provide sufficient insight into correlations and overview aspects. They lack sophisticated visualization, navigation and data reduction techniques. Our research goal is to find novel and adapt existing methods of visual analytics (VA) and information visualization (InfoVis) to support the process of analyzing in-car communication networks. With a set of prototypes and their evaluation, we managed to provide concrete solutions and verify how in-car communication analysis can benefit form research in VA and InfoVis.
I will talk about two recent works in the realm of novel mapping interfaces.
1) Street Slide -- Browsing Street Level Imagery
Title: Uncertain Isocontours
Almost all scientific data is affected by uncertainty. Visualization techniques that consider uncertainties therefore are urgently needed. In this talk I will focus on scalar fields as input data. For analysis of such fields, usually topological or geometrical features are extracted and displayed. The most prominent features in scalar fields are isocontours. A means to describe how errors in the input data are amplified during feature extraction is numerical condition. Applying this to isocontours, the sensitivity of isocontours to changes in the input data can be computed and displayed. Furthermore, the average condition number can aid the selection of isovalues that correspond to isocontours that are particularly robust.