The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform

Changick Kim - One of the best experts on this subject based on the ideXlab platform.

  • adaptive post filtering for reducing blocking and ringing artifacts in low bit rate video coding
    Signal Processing-image Communication, 2002
    Co-Authors: Changick Kim
    Abstract:

    Abstract In this paper, we present a method to reduce blocking and ringing artifacts in low bit-rate block-based video coding. For each block, its DC value and DC values of the surrounding eight neighbor blocks are exploited to predict low frequency AC coefficients, which allow to infer spatial characteristics of a block before quantization stage in the encoding system. These predicted AC coefficients are used to classify each block into either of two categories, low-activity or high-activity block. In the following post-processing stage, two kinds of low pass filters are adaptively applied according to the classified result on each block. It allows for strong low pass filtering in low-activity regions where the blocking artifacts are most noticeable, whereas it allows for weak low pass filtering in high-activity regions to reduce ringing noise as well as blocking artifacts without introducing undesired blur. In the former case, the blocking artifacts are reduced by one-dimensional (1-D) horizontal and vertical low pass filters. In the latter case, both deblocking and deringing are considered by using either 3-tap or 2-tap filter, which make the Architecture Simple. TMN8 decoder for H.263+ is used to test the proposed method. The experimental results are evaluated in both subjective and objective manner, and show that the proposed algorithm is efficient and effective in reducing ringing artifacts as well as blocking artifacts in the low bit-rate block-based video coding.

  • adaptive post filtering for reducing blocking and ringing artifacts in low bit rate video coding
    Image processing. Conference, 2002
    Co-Authors: Changick Kim
    Abstract:

    In this paper, we present a method to reduce blocking and ringing artifacts in low bit-rate block-based video coding. For each block, its DC value and DC values of the surrounding eight neighbor blocks are exploited to predict low frequency AC coefficients. Those predicted AC coefficients allow to infer spatial characteristics of a block before quantization stage in the encoding system. They are used to classify each block into either of two categories, low-activity and high-activity block. In the following post-processing stage, two kinds of low pass filters are adaptively applied according to the classified result on each block. It allows for strong low pass filtering in low-activity regions where the blocking artifacts are most noticeable, whereas it allows for weak low pass filtering in high-activity regions to reduce ringing noise as well as blocking artifacts without introducing undesired blur. In the former case, the blocking artifacts are reduced by one dimensional (1-D) horizontal and vertical low pass filters, and selective use of horizontal/vertical direction is adopted depending on the absolute values of the predicted AC coefficients. In the latter case, deblocking and deringing is conducted by a single filter, which makes the Architecture Simple. TMN8 decoder for H.263+ is used to test the proposed method. The experimental results show that the proposed algorithm is efficient and effective in reducing ringing artifacts as well as blocking artifacts from the low bit-rate block-based video coding.

Mark Gahegan - One of the best experts on this subject based on the ideXlab platform.

  • geovista studio a codeless visual programming environment for geoscientific data analysis and visualization
    Computers & Geosciences, 2002
    Co-Authors: Masahiro Takatsuka, Mark Gahegan
    Abstract:

    The fundamental goal of the GeoVISTA Studio project is to improve geoscientific analysis by providing an environment that operationally integrates a wide range of analysis activities, including those both computationally and visually based. Improving the infrastructure used in analysis has far-reaching potential to better integrate human-based and computationally based expertise, and so ultimately improve scientific outcomes. To address these challenges, some difficult system design and software engineering problems must be overcome.This paper illustrates the design of a component-oriented system, GeoVISTA Studio, as a means to overcome such difficulties by using state-of-the-art component-based software engineering techniques. Advantages described include: ease of program construction (visual programming), an open (non-proprietary) Architecture, Simple component-based integration and advanced deployment methods. This versatility has the potential to change the nature of systems development for the geosciences, providing better mechanisms to coordinate complex functionality, and as a consequence, to improve analysis by closer integration of software tools and better engagement of the human expert. Two example applications are presented to illustrate the potential of the Studio environment for exploring and better understanding large, complex geographical datasets and for supporting complex visual and computational analysis.

  • WISE (2) - Exploratory geospatial analysis using GeoVISTA Studio: from a desktop to the Web
    Proceedings of the Second International Conference on Web Information Systems Engineering, 1
    Co-Authors: Masahiro Takatsuka, Mark Gahegan
    Abstract:

    The main objective of the GeoVISTA Studio project is to improve geoscientific analysis by providing an environment that operationally integrates a wide range of analysis activities, including those both computationally and visually based. We argue that improving the infrastructure used in analysis has far-reaching potential to better integrate human-based and computationally-based expertise, whether locally or remotely available, and so ultimately improve scientific outcomes. The improvements to research infrastructure proposed have implications for Web-based deployment of analysis methods. This paper illustrates various features of GeoVISTA Studio, such as ease of program construction (visual programming), an open (non-proprietary) Architecture, Simple component-based integration and advanced deployment methods, which allow us to rapidly construct and share applications that combine geocomputation and geovisualization methods. It also demonstrates that GeoVISTA Studio can be used as both a Web GIS application and a Web GIS application builder.

Antonio Isalgue - One of the best experts on this subject based on the ideXlab platform.

  • The Mediterranean blind: Less light, better vision
    Renewable Energy, 1998
    Co-Authors: Helena Coch, Rafael Serra, Antonio Isalgue
    Abstract:

    Abstract The mediterranean blind is one of the most efficient and sophisticated technical system to allow natural illumination in building. A Simple solution permits good visual conditions with low heat gains and high ventilation. This solution shows how in Architecture, Simple designs following thoroughly understood principles can achieve far more suitable environment results than high-tech solution applied without criteria

  • The Mediterranean blind: Less light, better vision
    Renewable Energy, 1998
    Co-Authors: Helena Coch, Rafael Serra, Antonio Isalgue
    Abstract:

    The mediterranean blind is one of the most efficient and sophisticated technical system to allow natural illumination in building. A Simple solution permits good visual conditions with low beat gains and high ventilation. This solution shows how in Architecture, Simple designs following thoroughly understood principles can achieve far more suitable environment results than high-tech solution applied without criteria.Postprint (published version

Masahiro Takatsuka - One of the best experts on this subject based on the ideXlab platform.

  • geovista studio a codeless visual programming environment for geoscientific data analysis and visualization
    Computers & Geosciences, 2002
    Co-Authors: Masahiro Takatsuka, Mark Gahegan
    Abstract:

    The fundamental goal of the GeoVISTA Studio project is to improve geoscientific analysis by providing an environment that operationally integrates a wide range of analysis activities, including those both computationally and visually based. Improving the infrastructure used in analysis has far-reaching potential to better integrate human-based and computationally based expertise, and so ultimately improve scientific outcomes. To address these challenges, some difficult system design and software engineering problems must be overcome.This paper illustrates the design of a component-oriented system, GeoVISTA Studio, as a means to overcome such difficulties by using state-of-the-art component-based software engineering techniques. Advantages described include: ease of program construction (visual programming), an open (non-proprietary) Architecture, Simple component-based integration and advanced deployment methods. This versatility has the potential to change the nature of systems development for the geosciences, providing better mechanisms to coordinate complex functionality, and as a consequence, to improve analysis by closer integration of software tools and better engagement of the human expert. Two example applications are presented to illustrate the potential of the Studio environment for exploring and better understanding large, complex geographical datasets and for supporting complex visual and computational analysis.

  • WISE (2) - Exploratory geospatial analysis using GeoVISTA Studio: from a desktop to the Web
    Proceedings of the Second International Conference on Web Information Systems Engineering, 1
    Co-Authors: Masahiro Takatsuka, Mark Gahegan
    Abstract:

    The main objective of the GeoVISTA Studio project is to improve geoscientific analysis by providing an environment that operationally integrates a wide range of analysis activities, including those both computationally and visually based. We argue that improving the infrastructure used in analysis has far-reaching potential to better integrate human-based and computationally-based expertise, whether locally or remotely available, and so ultimately improve scientific outcomes. The improvements to research infrastructure proposed have implications for Web-based deployment of analysis methods. This paper illustrates various features of GeoVISTA Studio, such as ease of program construction (visual programming), an open (non-proprietary) Architecture, Simple component-based integration and advanced deployment methods, which allow us to rapidly construct and share applications that combine geocomputation and geovisualization methods. It also demonstrates that GeoVISTA Studio can be used as both a Web GIS application and a Web GIS application builder.

D.v. Rao - One of the best experts on this subject based on the ideXlab platform.

  • ICASSP - Highly parallel Architectures for solving linear equations
    ICASSP '81. IEEE International Conference on Acoustics Speech and Signal Processing, 1
    Co-Authors: Sun-yuan Kung, D.v. Rao
    Abstract:

    An important impact of the fast growing VLSI device technology will be the massive capability of parallel processing which will in turn greatly affect the trend of modern signal processing technology. For the new trend it will be a necessity to have revolutionary architectural design concepts such as topological mapping between algorithm and Architecture, Simple and regular data flow etc [1]. In this paper, based on a natural topology of the computing structure, a novel "computational wave-front" notion is introduced for describing and and validating data flow in locally connected networks. The parallel Architectures include the linear system, with and without pivoting, and the least-square solver using Givens method. We believe that this set of linear system Architectures will play a central role in modern signal processing.