• Title/Summary/Keyword: digital broadcast

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Blind Decision Feedback Equalizer with a Modified Trellis Decoder for ATSC DTV Receivers (ATSC DTV 수신기를 위해 변형된 트렐리스 복호기를 사용하는 블라인드 판정 궤환 등화기)

  • 박성익;김형남;김승원;이수인
    • Journal of Broadcast Engineering
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    • v.8 no.4
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    • pp.481-491
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    • 2003
  • We present a near-optimal blind decision feedback equalizer (DFE) for Advanced Television Systems Committee digital television (DTV) receivers. By adopting a modified trellis decoder (MTD) with trace back depth of 1 for the decision device In the DFE, we obtain a hardware-efficient near-optimal blind DFE approaching to the optimal DFE which has no error propagation. The MTD uses absolute distance instead of Euclidean distance for computation of a path metric, resulting. In reduced computational complexity. Comparing to the conventional slicer, the MTD shows outstanding performance improvement of decision error probability and is comparable to the original trellis decoder using Euclidean distance. Reducing error propagation in the DFE leads to the improvement of convergence performance in terms of convergence speed and residual error. Simulation results show that the proposed blind DFE performs much better than the blind DFE with the slicer.

Distributed Translator Part 3: Field Test Results (분산 중계기 Part 3: 필드 테스트 결과)

  • Park, Sung-Ik;Seo, Jae-Hyun;Eum, Ho-Min;Lee, Yong-Hoon;Kim, Heung-Mook
    • Journal of Broadcast Engineering
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    • v.15 no.1
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    • pp.40-51
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    • 2010
  • This paper presents and analyzes field test results of distributed translator (DTxR) for distributed frequency network (DFN) in the ATSC (Advanced Television Systems Committee) terrestrial digital TV broadcasting system. In the field test, according to types of antennas and receivers in areas where are overlapped by two DTxRs' coverage, we measured reception power, noise margin reception possibility, and ease of reception at each test point. By the field test results, when two DTxRs are on, reception power and noise margin are increased than when one DTxR is on. However, reception rate and ease of reception are similar or increased according to types of receivers.

Effective Utilization of DLNA Functions in Home Media Devices (홈 미디어 기기의 DLNA 소프트웨어 효율적 적용)

  • Kang, Ki-Cheol;Kim, Se-Young;Kim, Dae-Jin
    • Journal of Broadcast Engineering
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    • v.17 no.1
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    • pp.37-48
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    • 2012
  • These days many DLNA home media network services start in home network area. DLNA networking softwares included in DLNA media devices contains all of server, renderer and controller functions. But a home media device in home media network environment not uses all of DLNA functions but uses only limited functions. Using all of integrated DLNA functions wastes networking and processing resources especially in home media network, because a home media device uses very limited functions. For example, a smart-TV has a main role of playback and a network attached storage has a main role of media content storage. In this paper, we analyze integrated DLNA networking softwares and design DLNA software models representing each home media device so as to utilize device resources efficiently. And we implement DLNA softwares for smart-TV and smart-phone and test resource efficiency.

Overview and Performance Analysis of the Emerging Scalable Video Coding (스케일러블 비디오 부호화의 개요 및 성능 분석)

  • Choi, Hae-Chul;Lee, Kyung-Il;Kang, Jung-Woo;Bae, Seong-Jun;Yoo, Jeong-Ju
    • Journal of Broadcast Engineering
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    • v.12 no.6
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    • pp.542-554
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    • 2007
  • Seamless streaming of multimedia content via heterogeneous networks to viewers using a variety of devices has been a desire for many multimedia services, for which the multimedia contents should be adapted to usage environments such as network characteristics, terminal capabilities, and user preferences. Scalability in video coding is one of attractive features to meet dynamically changing requirements of heterogeneous networks. Currently a new scalable video coding (SVC) is standardizing in the Joint Video Team (JVT) of the ISO/IEC Moving Picture Experts Group (MPEG) and the ITU-T Video Coding Experts Group (VCEG), which will be released as Extension 3 of H.264/MPEG-4 AVC. In this paper, we introduce new technologies of SVC and evaluate performance of it especially regarding on overhead bit-rate and coding efficiency to support spatial, temporal, and quality scalability.

SIFT Feature Based Digital Watermarking Method for VR Image (VR영상을 위한 SIFT 특징점 기반 디지털 워터마킹 방법)

  • Moon, Won-Jun;Seo, Young-Ho;Kim, Dong-Wook
    • Journal of Broadcast Engineering
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    • v.24 no.6
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    • pp.1152-1162
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    • 2019
  • With the rapid development of the VR industry, many VR contents are produced and circulated, and the need for copyright protection is increasing. In this paper, we propose a method of embedding and extracting watermarks in consideration of VR production process. In embedding, SIFT is performed by selecting the region where distortion is minimized in VR production, and transformed into frequency domain using DWT and embedded into the QIM method. In extracting process, in order to correct the distortion in the projection process, the top and bottom regions are changed to different projection methods and some middle regions are rotated using 3DoF to extract the watermark. After this processing, extracted watermark has higher accuracy than the conventional watermark method, and the validity of the proposed watermark is shown by showing that the accuracy is maintained even in various attacks.

A Study on Conditional Access Message Multiplexing Method in T-DMB Conditional Access System (T-DMB 제한수신시스템에서 제한 수신 메시지 다중화 기법 연구)

  • Kim, Dong-Hyun;Seo, Hyung-Yoon;Bae, Byung-Jun;Kim, Jong-Deok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.722-724
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    • 2010
  • CAS(Conditional Access System) was developed for paid-for service in cable and fixed satellite broadcast system and technology and market maturity are high. However, these assessment is limited by CAS in fixed broadcasting system. In case of digital mobile broadcast such as T-DMB is difficult to apply CAS technology of fixed broadcasting system because of a use method and technology characteristic. Expecially, in case T-DMB using limited resources, a CAS message which must transmit in each service channel can cause problems. It is desirable that system transmits the CAS message which transmitted by each service channel through logical CAS message-only channel. In order to make a logical CAS message channel, we need a multiplexing techniques for CAS message using in each channel. In this paper, we design the CAS message multiplexing techniques for composition of CAS message-only channel.

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Analysis of drama viewership related words through unstructured data collection (비정형데이터 수집을 통한 드라마 시청률 연관어 분석)

  • Kang, Sun-Kyoung;Lee, Hyun-Chang;Shin, Seong-Yoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.8
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    • pp.1567-1574
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    • 2017
  • In this paper, we analyzed the stereotyped and non - stereotyped data in order to analyze the drama 's ratings. The formalized data collection collected 19 items from the four areas of drama information, person information, broadcasting information, and audience rating information of each broadcasting company. Atypical data were collected from bulletin boards, pre - broadcast blogs and post - broadcast blogs operated by each broadcasting company using a crawling technique. As a result of comparing the differences according to the four areas for each broadcaster from the collected regular data, the results were similar to each other. And we derived seven related words by analyzing the correlation of occurrence frequencies from unstructured data collected from bulletin boards and blogs of each broadcasting company. The derived associations were obtained through reliability analysis.

A Study on the Method of Creating Realistic Content in Audience-participating Performances using Artificial Intelligence Sentiment Analysis Technology (인공지능 감정분석 기술을 이용한 관객 참여형 공연에서의 실감형 콘텐츠 생성 방식에 관한 연구)

  • Kim, Jihee;Oh, Jinhee;Kim, Myeungjin;Lim, Yangkyu
    • Journal of Broadcast Engineering
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    • v.26 no.5
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    • pp.533-542
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    • 2021
  • In this study, a process of re-creating Jindo Buk Chum, one of the traditional Korean arts, into digital art using various artificial intelligence technologies was proposed. The audience's emotional data, quantified through artificial intelligence language analysis technology, intervenes in various object forms in the projection mapping performance and affects the big story without changing it. If most interactive arts express communication between the performer and the video, this performance becomes a new type of responsive performance that allows the audience to directly communicate with the work, centering on artificial intelligence emotion analysis technology. This starts with 'Chuimsae', a performance that is common only in Korean traditional art, where the audience directly or indirectly intervenes and influences the performance. Based on the emotional information contained in the performer's 'prologue', it is combined with the audience's emotional information and converted into the form of images and particles used in the performance to indirectly participate and change the performance.

Extremely High-Definition Computer Generated Hologram Calculation Algorithm with Concave Lens Function (오목 렌즈 함수를 이용한 초 고해상도 Computer generated hologram 생성 기법)

  • Lee, Chang-Joo;Choi, Woo-Young;Oh, Kwan-Jung;Hong, Keehoon;Choi, Kihong;Cheon, Sang-Hoon;Park, Joongki;Lee, Seung-Yeol
    • Journal of Broadcast Engineering
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    • v.25 no.6
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    • pp.836-844
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    • 2020
  • A very large number of pixels is required to generate a computer generated hologram (CGH) with a large-size and wide viewing angle equivalent to that of an analog hologram, which incurs a very large amount of computation. For this reason, a high-performance computing device and long computation time were required to generate high-definition CGH. To solve these problems, in this paper, we propose a technique for generating high-definition CGH by arraying the pre-calculated low-definition CGH and multiplying the appropriately-shifted concave lens function. Using the proposed technique, 0.1 Gigapixel CGH recorded by the point cloud method can be used to calculate 2.5 Gigapixels CGH at a very high speed, and the recorded hologram image was successfully reconstructed through the experiment.

SPIHT-based Subband Division Compression Method for High-resolution Image Compression (고해상도 영상 압축을 위한 SPIHT 기반의 부대역 분할 압축 방법)

  • Kim, Woosuk;Park, Byung-Seo;Oh, Kwan-Jung;Seo, Young-Ho
    • Journal of Broadcast Engineering
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    • v.27 no.2
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    • pp.198-206
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    • 2022
  • This paper proposes a method to solve problems that may occur when SPIHT(set partition in hierarchical trees) is used in a dedicated codec for compressing complex holograms with ultra-high resolution. The development of codecs for complex holograms can be largely divided into a method of creating dedicated compression methods and a method of using anchor codecs such as HEVC and JPEG2000 and adding post-processing techniques. In the case of creating a dedicated compression method, a separate conversion tool is required to analyze the spatial characteristics of complex holograms. Zero-tree-based algorithms in subband units such as EZW and SPIHT have a problem that when coding for high-resolution images, intact subband information is not properly transmitted during bitstream control. This paper proposes a method of dividing wavelet subbands to solve such a problem. By compressing each divided subbands, information throughout the subbands is kept uniform. The proposed method showed better restoration results than PSNR compared to the existing method.