Results 221 to 230 of about 65,315 (261)

High Indexing Compression for Spatial Databases

2008 IEEE 8th International Conference on Computer and Information Technology Workshops, 2008
The KDB-tree is a traditional point access method for retrieving multidimensional data. Many literatures frequently address the low storage utilization and insufficient retrieval performance as two bottlenecks for KDB-tree family of structures. A large amount of unnecessary splits caused by data insertion orders and data skewness is the fatal reason ...
null Hung-Yi Lin, null Shih-Ying Chen
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Linear compression for spatially-varying BRDFs

Proceedings of the ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games, 2012
The storage requirements for rendering with arbitrary tabular BRDFs can be quite large. This limits the number of BRDFs that can be in used in a scene to only a few. Furthermore, material parameters can be too complex to store and render per-pixel.
Braeger, Steven, Hughes, Charles E.
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Compressed FEC Codes With Spatial-Coupling

IEEE Communications Letters, 2017
An error floor problem is observed for a spatially coupled sparse-regression (SCSR) code with limited sparsity in low-to-medium rates. This letter presents a scheme that also involves spatial-coupling and compressed-sensing (SCCS) similar to SCSR. We replace position modulation in SCSR by a general concatenated forward error control code.
Chulong Liang, Junjie Ma, Li Ping
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Spatial Data Compression Techniques for GML

2008 Japan-China Joint Workshop on Frontier of Computer Science and Technology, 2008
The Geography Markup Language (GML) has been introduced to standardize the representation of geographical data in Extensible Markup Language (XML), which makes the exchanging and sharing of geographical information easier. As GML becomes the geospatial language of the Web, the compression of GML files becomes a new challenge to the compression research
Yuzhen Li, Takashi Imaizumi, Jihong Guan
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Spatial-spectral encoded compressive hyperspectral imaging

ACM Transactions on Graphics, 2014
This paper proposes a novel compressive hyperspectral (HS) imaging approach that allows for high-resolution HS images to be captured in a single image. The proposed architecture comprises three key components: spatial-spectral encoded optical camera design, over-complete HS dictionary learning and sparse-constraint computational reconstruction.
Xing Lin, Yebin Liu, Jiamin Wu, Qionghai Dai   +3 more
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Spatially Separated Non-linear Pulse Compression

CLEO: 2014, 2014
We demonstrate the coherent combination of two solid-core fibers, which are used for nonlinear spectral broadening followed by temporal recompression. 320 fs input pulses coming from a fiber CPA system are split up and independently broadened in the two spatially separated fibers, hence, limitations of individual fibers are lifted.
Arno Klenke, Steffen Hädrich, Jens Limpert, Andreas Tünnermann   +3 more
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Visual Time Compression: Spatial and Temporal Cues

Human Factors: The Journal of the Human Factors and Ergonomics Society, 1975
Previous research has demonstrated the improved target detection performance resulting from the coherent motion cues provided by a visually time-compressed radar display (Moll and Scanlan, 1972; Scanlan, Roscoe, and Williges, 1971). These studies indicate that, as the detection task becomes more difficult because of increased noise and clutter, the ...
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Spatial compression of Seasat SAR imagery

IEEE Transactions on Geoscience and Remote Sensing, 1988
The results of a study of the techniques for spatial compression of synthetic-aperture-radar (SAR) imagery are summarized. Emphasis is on image-data volume reduction for archive and online storage applications while preserving the image resolution and radiometric fidelity. A quantitative analysis of various techniques, including vector quantization (VQ)
C.Y. Chang, R. Kwok, J.C. Curlander
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Spatial Texture Models for Video Compression

2007 IEEE International Conference on Image Processing, 2007
In this paper we integrate several spatial texture tools into a texture-based video coding scheme. We implemented texture techniques and segmentation strategies in order to detect texture regions in video sequences. These textures are analyzed using temporal motion techniques and are labeled as skipped areas that are not encoded.
Marc Bosch, Fengqing Zhu, Edward J. Delp
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Compressed sensing in spatial MIMO channels

2011 2nd International Conference on Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology (Wireless VITAE), 2011
Many wireless channels exhibit sparse multipath feature in practice. In this paper, we analyze the sparsity of sparse MIMO channel and the leakage effect with fixed Fourier basis in the spatial/angular domain. In order to enhance the sparsity of the MIMO angular channels we propose an optimized overcomplete Fourier basis dictionary, which is obtained ...
Wei Lu, Yingzhuang Liu, Desheng Wang
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