• Title/Summary/Keyword: Digital Audio

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The Study on Implementation of Receiver for Terrestrial DMB (지상파 DMB방송 수신기 개발에 관한 연구)

  • Won, Young-Jin;Na, Hee-Su
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.1011-1012
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    • 2006
  • In this paper, implementation process of standard platform for T-DMB Receiver in low-cost and small-size are following: First, implement SoC for 32 bit RISC CPU and 16 bit DSP, Hardware H.264 CODEC, Post Processor or Video Display, Audio Processor, I/O Device. Second, implement Real Time OS for flexible application. Third, propose simple architecture for interface with peripheral devices using one-chip processor.

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Secret Key Watermarking for Image Authentication

  • Woo, Chan-Il;In-Chul shin
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.815-818
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    • 2000
  • As the growth of internet and the diffusion of wide multimedia applications are increased, the ownership verification and authentication in communication channel for a digital image become more important. For these purpose there are many watermarking scheme available for image, video stream and audio data. In this paper we studied on techniques for integrity and authentication of digital images and proposed new watermarking algorithm. The proposed algorithm is implemented in C language on IBM-PC and the test results are shown.

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DVD(Digital Versatile Disk) 기술현황 및 시장 전망

  • 이영우
    • The Magazine of the IEIE
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    • v.23 no.7
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    • pp.37-43
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    • 1996
  • DVD(Digital Versatile Disk)는 CD(Compact Disk)에 비해 약 9배의 저장용량(4.7GByte)을 갖는 디스크로 멀티미디어 시대를 위한 최적의 기록 매채로 그 중요성이 부각되고 있다. Player의 용도 또한 가전 영역인 audio/video system과 computer영역인 DVD-ROM모두에 적용될뿐만 아니라 기존의 모든 CD도 호환되도록 하고 있어 DVD판매 시장이 매우 크게 형성될 것으로 예측하고 있다. 여기에서는 DVD요소 기술과 동향 및 전망, 규격 내용, 그리고 DVD의 시장 동향에 관하여 기술하고자 한다.

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Design of a Format Converter from MPEG-4 Over MPEG-2 TS to MP4 (MPEG-4 Over MPEG-2 TS로부터 MP4 파일로의 포맷 변환기 설계)

  • 최재영;정제창
    • Journal of Broadcast Engineering
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    • v.5 no.2
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    • pp.176-187
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    • 2000
  • MPEG-4 is a digital bit stream format and associated protocols for representing multimedia content consisting of natural and synthetic audio, video and object data. This paper describes an application where multiple audio/visual data stream are combined in MPEG-4 and transported via MPTG-2 transport streams(TS). Also, this paper describes how to convert MPEG-4 Over MPEG-2 TS bit streams into MP4 file which Is designed to contain the media information of an MPEG-4 presentation in a flexible, extensible format. MPEG-4 is presented in the form of audio-visual objects that are arranged into an audio-visual scene by means of a scene descriptor and is composed of the audio-visual objects by means of an object descriptor. These descriptor streams are not defined MPEG-2 TS. So. this paper focuses on handling of these descriptors and parsing TS streams to get MPEG-4 data. The MPEG-4 Over MPEG-2 TS to MP4 format converter is implemented in the demonstrated systems.

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Online Monaural Ambient Sound Extraction based on Nonnegative Matrix Factorization Method for Audio Contents (오디오 컨텐츠를 위한 비음수 행렬 분해 기법 기반의 실시간 단일채널 배경 잡음 추출 기법)

  • Lee, Seokjin
    • Journal of Broadcast Engineering
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    • v.19 no.6
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    • pp.819-825
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    • 2014
  • In this paper, monaural ambient component extraction algorithm based on nonnegative matrix factorization (NMF) is described. The ambience component extraction algorithm in this paper is developed for audio upmixing system; Recent researches have shown that they can enhance listener envelopment if the extracted ambient signal is applied into the multichannel audio upmixing system. However, the conventional method stores all of the audio signal and processes all at once, so it cannot be applied to streaming system and digital signal processor (DSP) system. In this paper, the ambient component extraction algorithm based on on-line nonnegative matrix factorization is developed and evaluated to solve the problem. As a result of analysis of the processed signal with spectral flatness measures in the experiment, it was shown that the developed system can extract the ambient signal similarly with the conventional batch process system.

A Stereo Audio DAC with Asymmetric PWM Power Amplifier (비대칭 펄스 폭 변조 파워-앰프를 갖는 스테레오 오디오 디지털-아날로그 변환기)

  • Lee, Yong-Hee;Jun, Young-Hyun;Kong, Bai-Sun
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.7
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    • pp.44-51
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    • 2008
  • A stereo audio digital-to-analog converter (DAC) with a power amplifier using asymmetric pulse-width modulation (PWM) is presented. To adopt class-D amplifier mainly used in high-power audio appliances for head-phones application, this work analyzes the noise caused by the inter-channel interference during the integration and optimizes the design of the sigma-delta modulator to decrease the performance degradation caused by the noise. The asymmetric PWM is implemented to reduce switching noise and power loss generated from the power amplifier. This proposed architecture is fabricated in 0.13-mm CMOS technology. The proposed audio DAC including the power amplifier with single-ended output achieves a dynamic range (DR) of 95-dB dissipating 4.4-mW.

A Study on Real-Time Loudness Metering Algorithm for Digital Broadcasting (디지털 방송용 오디오 레벨 계측 알고리즘의 실시간화 연구)

  • Park Seong-Gyoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.4 s.95
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    • pp.427-437
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    • 2005
  • In this paper, the perceived audio level metering algorithm of digital audio sound to be able to operate in real-time is proposed. Through analyzing a conventional recommendation ITU-RBS1387-I for objective audio quality analysis, FFT-based loudness metering algorithm is implemented and the real-time method of that algorithm was advised and proved. The proposed method is based on look-up table. In order to prove the proved method, using 23 pure tones and 30 preselected digital audio samples, its performance and operation time is evaluated. Its performance, compared with an original algorithm's, have a good figure of less than $2\;\%$ error even if look-up table related with spectral spreading have large level resolution of $10\;\cal{dB}$. The proposed algorithm take only 1/21 of original algorithm's measuring time. Also, in the proposed algorithm auditory pitch group energy calculation take 1/450 of original algorithm's and excitation calculation take 1/3.57. In conclusion, the proposed algorithm is expected to be implemented into DSP-based real-time loudness meter.

Interference Analysis from S-DAB into T-IMT-2000 in 2630-2655MHz

  • Kang B. S.
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.792-795
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    • 2004
  • This paper is an interference analysis from S-DAB(Satellite-Digital Audio Broadcasting) into terrestrial IMT-2000 systems intending to use the band 2630-2 655 MHz and that could be used to determine the impact of S­DAB on terrestrial IMT-2000 in the context of co-frequency sharing through the development of pfd masks.

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밀레니엄 시대의 방송관련 가전제품의 전망

  • 김영길
    • Broadcasting and Media Magazine
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    • v.5 no.2
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    • pp.65-71
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    • 2000
  • 가정용 AV(audio video)기기는 방송 수신기를 디스플레이 장치로서 사용하고 있기 때문에 방송기술과 밀접한 관계를 가지고 있다. 새 밀레니엄 시대의 디지털 방송기술에 대응한 AV가전기기는 digital network, software의 3가지 단어로 설명할 수 있다. 본 논문에서는 디지털 방송 시대의 AV가전기기의 개념을 다루어 보았다.

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A Practical Digital Video Database based on Language and Image Analysis

  • Liang, Yiqing
    • Proceedings of the Korea Database Society Conference
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    • 1997.10a
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    • pp.24-48
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    • 1997
  • . Supported byㆍDARPA′s image Understanding (IU) program under "Video Retrieval Based on Language and image Analysis" project.DARPA′s Computer Assisted Education and Training Initiative program (CAETI)ㆍObjective: Develop practical systems for automatic understanding and indexing of video sequences using both audio and video tracks(omitted)

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