The Experts below are selected from a list of 183 Experts worldwide ranked by ideXlab platform
T.e. Tremain - One of the best experts on this subject based on the ideXlab platform.
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Progress towards a new Government Standard 2400 bps voice coder
1995 International Conference on Acoustics Speech and Signal Processing, 1995Co-Authors: M.a. Kohler, L.m. Supplee, T.e. TremainAbstract:In order to support the need for higher quality low rate voice communications for Government, industry, and military customers, the United States Government is conducting a search for a new voice compression algorithm at 2400 bits per second (bps). The United States Department of Defense Digital Voice Processing Consortium (DDVPC), consisting of members from civilian and military branches of the US Government, is directing the testing and evaluation of several candidate 2400 bps algorithms. The goal of the DDVPC is to select a new algorithm which meets or exceeds the published requirements by mid 1996. The selected algorithm, to become the new Standard, should be implementable in a small, low powered device by 1997. This paper describes the status of the testing and evaluation process from its beginning in early 1993 through the end of 1994.
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ICASSP - Progress towards a new Government Standard 2400 bps voice coder
1995 International Conference on Acoustics Speech and Signal Processing, 1995Co-Authors: M.a. Kohler, L.m. Supplee, T.e. TremainAbstract:In order to support the need for higher quality low rate voice communications for Government, industry, and military customers, the United States Government is conducting a search for a new voice compression algorithm at 2400 bits per second (bps). The United States Department of Defense Digital Voice Processing Consortium (DDVPC), consisting of members from civilian and military branches of the US Government, is directing the testing and evaluation of several candidate 2400 bps algorithms. The goal of the DDVPC is to select a new algorithm which meets or exceeds the published requirements by mid 1996. The selected algorithm, to become the new Standard, should be implementable in a small, low powered device by 1997. This paper describes the status of the testing and evaluation process from its beginning in early 1993 through the end of 1994.
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A New Government Standard 2400 bps Speech Coder
Proceedings. IEEE Workshop on Speech Coding for Telecommunications, 1993Co-Authors: V.c. Welch, T.e. TremainAbstract:The US Goverment is seeking a new 2400 bps speech coding algorithm. Researchers, contractors, and institutions are invited to participate in a cooperative effort to develop this Standard. It is our hope that this Standard will significantly enhance global secure voice communications, offering high quality coding at 2400 bps.
T.p. Barnwell - One of the best experts on this subject based on the ideXlab platform.
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A mixed excitation LPC vocoder model for low bit rate speech coding
IEEE Transactions on Speech and Audio Processing, 1995Co-Authors: A.v. Mccree, T.p. BarnwellAbstract:Traditional pitch-excited linear predictive coding (LPC) vocoders use a fully parametric model to efficiently encode the important information in human speech. These vocoders can produce intelligible speech at low data rates (800-2400 b/s), but they often sound synthetic and generate annoying artifacts such as buzzes, thumps, and tonal noises. These problems increase dramatically if acoustic background noise is present at the speech input. This paper presents a new mixed excitation LPC vocoder model that preserves the low bit rate of a fully parametric model but adds more free parameters to the excitation signal so that the synthesizer can mimic more characteristics of natural human speech. The new model also eliminates the traditional requirement for a binary voicing decision so that the vocoder performs well even in the presence of acoustic background noise. A 2400-b/s LPC vocoder based on this model has been developed and implemented in simulations and in a real-time system. Formal subjective testing of this coder confirms that it produces natural sounding speech even in a difficult noise environment. In fact, diagnostic acceptability measure (DAM) test scores show that the performance of the 2400-b/s mixed excitation LPC vocoder is close to that of the Government Standard 4800-b/s CELP coder.
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Implementation and evaluation of a 2400 bit/s mixed excitation LPC vocoder
1993 IEEE International Conference on Acoustics Speech and Signal Processing, 1993Co-Authors: A.v. Mccree, T.p. BarnwellAbstract:The authors present an LPC (linear predictive coding) vocoder model with four features: mixed pulse and noise excitation, periodic or aperiodic pulses, pulse dispersion filter, and adaptive spectral enhancement. A 2400-bit/s speech coder based on this model has been implemented, as well as a 4800-bit/s coder which also includes Fourier series spectral information. Formal subjective test results show that this 2400-bit/s vocoder performs better than the Government Standard at the same bit rate, for both clean and noisy input speech. The quality of this coder approaches that of the higher-rate CELP (code-excited linear prediction) Standard. The addition of Fourier magnitudes to the 4800-bit/s coder provides significant improvement, but both the bit rate and the computational requirements of the 4800-bit/s coder are much higher than for the 2400-bit/s vocoder. Therefore, this 4800-bit/s coder may not be as useful, but its performance does serve as a target for possible improvements to the parametric model.
Gooseon Yoon - One of the best experts on this subject based on the ideXlab platform.
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linkage of ogc wps 2 0 to the e Government Standard framework in korea an implementation case for geo spatial image processing
ISPRS international journal of geo-information, 2017Co-Authors: Gooseon YoonAbstract:There are many cases wherein services offered in geospatial sectors are integrated with other fields. In addition, services utilizing satellite data play important roles in daily life and in sectors such as environment and science. Therefore, a management structure appropriate to the scale of the system should be clearly defined. The motivation of this study is to resolve issues, apply Standards related to a target system, and provide practical strategies with a technical basis. South Korea uses the e-Government Standard Framework, using the Java-based Spring framework, to provide guidelines and environments with common configurations and functions for developing web-based information systems for public services. This web framework offers common sources and resources for data processing and interface connection to help developers focus on business logic in designing a web system. In this study, a geospatial image processing system—linked with the Open Geospatial Consortium (OGC) Web Processing Service (WPS) 2.0 Standard for real geospatial information processing, and based on this Standard framework—was designed and built utilizing fully open sources. This is the first case of implementation based on WPS 2.0 running on the e-Government Standard Framework. Establishing a Standard for its use will be important, and the system built in this study can serve as a reference for the foundational architecture in building geospatial web service systems with geodata-processing functionalities in Government agencies.
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Design and implementation of geo-spatial image processing system using OGC WPS 2.0 and Web framework on Openstack cloud
2016 4th International Workshop on Earth Observation and Remote Sensing Applications (EORSA), 2016Co-Authors: Gooseon YoonAbstract:Recently, OGC Standards for geo-spatial data and information such as Web Map Service (WMS), Web Feature Service (WFS), Web Coverage Service (WCS) strengthen their extension and expansion of geo-based applications. As well, Web Processing Service (WPS) provides the interface specification regarding on-line geo-processing among inter-connecting systems complying with this Standard. While, one of current huge trends, cloud computing means pay-as-you-go type uses of any computing resources including server, networking, or storage capacity. This gradually affects web-based information systems as software-as-a-service, infrastructure-as-a-service or platform-as-a-service in all fields. Many cloud environments are available in commercial or free basis. Amazon, Microsoft, IBM and Google are positioning as so-called cloud bursting service companies. By the way, cloud computing based on open source is also an important aspect for system developers. OpenStack is a typical example, and it applies to build public, private or hybrid cloud system in most application areas. There are a few practical cases in the geo-spatial application implementation by cloud computing environment, yet. As another thing for web-based applications, web framework is worth developers' consideration, because of its advantages of avoiding development redundancy and ensuring system stability. Therefore, it provides technical bases and implementation specifications for e-Government Standard web framework, in some countries. Spring framework, open source web framework, is an example. This study contains these three aspects: OGC WPS, OpenStack cloud, and Spring framework. Web is a very basic environment for information retrieval and processing so that it is also core to information system for geo-based data. However, approach to integrate and link with these three aspects is globally very early research stage now. These three components were integrated for the task of on-line geo-based image processing system implementation based on open source strategy. Above all, cloud computing environment using OpenStack was built to provide platform to deal with other components. Then, web framework was implemented onto this cloud environment to mediate client requesting and server responding via WPS. It is thought that this result can be a technical referential model for web-based geo-spatial applications including complex geo-data processing units between remote data providers and data processing server through Standard interfaces.
A.v. Mccree - One of the best experts on this subject based on the ideXlab platform.
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A mixed excitation LPC vocoder model for low bit rate speech coding
IEEE Transactions on Speech and Audio Processing, 1995Co-Authors: A.v. Mccree, T.p. BarnwellAbstract:Traditional pitch-excited linear predictive coding (LPC) vocoders use a fully parametric model to efficiently encode the important information in human speech. These vocoders can produce intelligible speech at low data rates (800-2400 b/s), but they often sound synthetic and generate annoying artifacts such as buzzes, thumps, and tonal noises. These problems increase dramatically if acoustic background noise is present at the speech input. This paper presents a new mixed excitation LPC vocoder model that preserves the low bit rate of a fully parametric model but adds more free parameters to the excitation signal so that the synthesizer can mimic more characteristics of natural human speech. The new model also eliminates the traditional requirement for a binary voicing decision so that the vocoder performs well even in the presence of acoustic background noise. A 2400-b/s LPC vocoder based on this model has been developed and implemented in simulations and in a real-time system. Formal subjective testing of this coder confirms that it produces natural sounding speech even in a difficult noise environment. In fact, diagnostic acceptability measure (DAM) test scores show that the performance of the 2400-b/s mixed excitation LPC vocoder is close to that of the Government Standard 4800-b/s CELP coder.
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Implementation and evaluation of a 2400 bit/s mixed excitation LPC vocoder
1993 IEEE International Conference on Acoustics Speech and Signal Processing, 1993Co-Authors: A.v. Mccree, T.p. BarnwellAbstract:The authors present an LPC (linear predictive coding) vocoder model with four features: mixed pulse and noise excitation, periodic or aperiodic pulses, pulse dispersion filter, and adaptive spectral enhancement. A 2400-bit/s speech coder based on this model has been implemented, as well as a 4800-bit/s coder which also includes Fourier series spectral information. Formal subjective test results show that this 2400-bit/s vocoder performs better than the Government Standard at the same bit rate, for both clean and noisy input speech. The quality of this coder approaches that of the higher-rate CELP (code-excited linear prediction) Standard. The addition of Fourier magnitudes to the 4800-bit/s coder provides significant improvement, but both the bit rate and the computational requirements of the 4800-bit/s coder are much higher than for the 2400-bit/s vocoder. Therefore, this 4800-bit/s coder may not be as useful, but its performance does serve as a target for possible improvements to the parametric model.
M.a. Kohler - One of the best experts on this subject based on the ideXlab platform.
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Progress towards a new Government Standard 2400 bps voice coder
1995 International Conference on Acoustics Speech and Signal Processing, 1995Co-Authors: M.a. Kohler, L.m. Supplee, T.e. TremainAbstract:In order to support the need for higher quality low rate voice communications for Government, industry, and military customers, the United States Government is conducting a search for a new voice compression algorithm at 2400 bits per second (bps). The United States Department of Defense Digital Voice Processing Consortium (DDVPC), consisting of members from civilian and military branches of the US Government, is directing the testing and evaluation of several candidate 2400 bps algorithms. The goal of the DDVPC is to select a new algorithm which meets or exceeds the published requirements by mid 1996. The selected algorithm, to become the new Standard, should be implementable in a small, low powered device by 1997. This paper describes the status of the testing and evaluation process from its beginning in early 1993 through the end of 1994.
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ICASSP - Progress towards a new Government Standard 2400 bps voice coder
1995 International Conference on Acoustics Speech and Signal Processing, 1995Co-Authors: M.a. Kohler, L.m. Supplee, T.e. TremainAbstract:In order to support the need for higher quality low rate voice communications for Government, industry, and military customers, the United States Government is conducting a search for a new voice compression algorithm at 2400 bits per second (bps). The United States Department of Defense Digital Voice Processing Consortium (DDVPC), consisting of members from civilian and military branches of the US Government, is directing the testing and evaluation of several candidate 2400 bps algorithms. The goal of the DDVPC is to select a new algorithm which meets or exceeds the published requirements by mid 1996. The selected algorithm, to become the new Standard, should be implementable in a small, low powered device by 1997. This paper describes the status of the testing and evaluation process from its beginning in early 1993 through the end of 1994.
