42,425 research outputs found
Layout of Multiple Views for Volume Visualization: A User Study
Abstract. Volume visualizations can have drastically different appearances when viewed using a variety of transfer functions. A problem then occurs in trying to organize many different views on one screen. We conducted a user study of four layout techniques for these multiple views. We timed participants as they separated different aspects of volume data for both time-invariant and time-variant data using one of four different layout schemes. The layout technique had no impact on performance when used with time-invariant data. With time-variant data, however, the multiple view layouts all resulted in better times than did a single view interface. Surprisingly, different layout techniques for multiple views resulted in no noticeable difference in user performance. In this paper, we describe our study and present the results, which could be used in the design of future volume visualization software to improve the productivity of the scientists who use it
Scale Stain: Multi-Resolution Feature Enhancement in Pathology Visualization
Digital whole-slide images of pathological tissue samples have recently
become feasible for use within routine diagnostic practice. These gigapixel
sized images enable pathologists to perform reviews using computer workstations
instead of microscopes. Existing workstations visualize scanned images by
providing a zoomable image space that reproduces the capabilities of the
microscope. This paper presents a novel visualization approach that enables
filtering of the scale-space according to color preference. The visualization
method reveals diagnostically important patterns that are otherwise not
visible. The paper demonstrates how this approach has been implemented into a
fully functional prototype that lets the user navigate the visualization
parameter space in real time. The prototype was evaluated for two common
clinical tasks with eight pathologists in a within-subjects study. The data
reveal that task efficiency increased by 15% using the prototype, with
maintained accuracy. By analyzing behavioral strategies, it was possible to
conclude that efficiency gain was caused by a reduction of the panning needed
to perform systematic search of the images. The prototype system was well
received by the pathologists who did not detect any risks that would hinder use
in clinical routine
The Design and Operation of The Keck Observatory Archive
The Infrared Processing and Analysis Center (IPAC) and the W. M. Keck
Observatory (WMKO) operate an archive for the Keck Observatory. At the end of
2013, KOA completed the ingestion of data from all eight active observatory
instruments. KOA will continue to ingest all newly obtained observations, at an
anticipated volume of 4 TB per year. The data are transmitted electronically
from WMKO to IPAC for storage and curation. Access to data is governed by a
data use policy, and approximately two-thirds of the data in the archive are
public.Comment: 12 pages, 4 figs, 4 tables. Presented at Software and
Cyberinfrastructure for Astronomy III, SPIE Astronomical Telescopes +
Instrumentation 2014. June 2014, Montreal, Canad
MITK-ModelFit: A generic open-source framework for model fits and their exploration in medical imaging -- design, implementation and application on the example of DCE-MRI
Many medical imaging techniques utilize fitting approaches for quantitative
parameter estimation and analysis. Common examples are pharmacokinetic modeling
in DCE MRI/CT, ADC calculations and IVIM modeling in diffusion-weighted MRI and
Z-spectra analysis in chemical exchange saturation transfer MRI. Most available
software tools are limited to a special purpose and do not allow for own
developments and extensions. Furthermore, they are mostly designed as
stand-alone solutions using external frameworks and thus cannot be easily
incorporated natively in the analysis workflow. We present a framework for
medical image fitting tasks that is included in MITK, following a rigorous
open-source, well-integrated and operating system independent policy. Software
engineering-wise, the local models, the fitting infrastructure and the results
representation are abstracted and thus can be easily adapted to any model
fitting task on image data, independent of image modality or model. Several
ready-to-use libraries for model fitting and use-cases, including fit
evaluation and visualization, were implemented. Their embedding into MITK
allows for easy data loading, pre- and post-processing and thus a natural
inclusion of model fitting into an overarching workflow. As an example, we
present a comprehensive set of plug-ins for the analysis of DCE MRI data, which
we validated on existing and novel digital phantoms, yielding competitive
deviations between fit and ground truth. Providing a very flexible environment,
our software mainly addresses developers of medical imaging software that
includes model fitting algorithms and tools. Additionally, the framework is of
high interest to users in the domain of perfusion MRI, as it offers
feature-rich, freely available, validated tools to perform pharmacokinetic
analysis on DCE MRI data, with both interactive and automatized batch
processing workflows.Comment: 31 pages, 11 figures URL: http://mitk.org/wiki/MITK-ModelFi
The Topology ToolKit
This system paper presents the Topology ToolKit (TTK), a software platform
designed for topological data analysis in scientific visualization. TTK
provides a unified, generic, efficient, and robust implementation of key
algorithms for the topological analysis of scalar data, including: critical
points, integral lines, persistence diagrams, persistence curves, merge trees,
contour trees, Morse-Smale complexes, fiber surfaces, continuous scatterplots,
Jacobi sets, Reeb spaces, and more. TTK is easily accessible to end users due
to a tight integration with ParaView. It is also easily accessible to
developers through a variety of bindings (Python, VTK/C++) for fast prototyping
or through direct, dependence-free, C++, to ease integration into pre-existing
complex systems. While developing TTK, we faced several algorithmic and
software engineering challenges, which we document in this paper. In
particular, we present an algorithm for the construction of a discrete gradient
that complies to the critical points extracted in the piecewise-linear setting.
This algorithm guarantees a combinatorial consistency across the topological
abstractions supported by TTK, and importantly, a unified implementation of
topological data simplification for multi-scale exploration and analysis. We
also present a cached triangulation data structure, that supports time
efficient and generic traversals, which self-adjusts its memory usage on demand
for input simplicial meshes and which implicitly emulates a triangulation for
regular grids with no memory overhead. Finally, we describe an original
software architecture, which guarantees memory efficient and direct accesses to
TTK features, while still allowing for researchers powerful and easy bindings
and extensions. TTK is open source (BSD license) and its code, online
documentation and video tutorials are available on TTK's website
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