• Title/Summary/Keyword: Inter-view prediction

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View Synthesis for Inter-view Prediction of 3D Video Coding (시점 생성 기법을 이용한 3차원 비디오 부호화의 시점 간 예측 기술)

  • Kim, Dong-Hyun;Seo, Jung-Dong;Ham, Bum-Seop;Choi, Jin-Wook;Sohn, Kwang-Hoon
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2010.07a
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    • pp.130-133
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    • 2010
  • 멀티미디어 신호 처리 분야의 급속한 발전으로 인해 3차원 TV(3DTV)는 차세대 방송 시스템 시장에서 가장 주목을 받는 제품이 되었다. 3DTV는 사용자에게 입체감을 제공하여 사용자가 마치 그곳에 있는 듯한 효과를 줄 수 있다. 이에 최근 다시점 컬러 영상과 그에 대응되는 깊이 영상을 이용하여 다양한 위치에서의 입체 영상을 제공하는 기술이 활발히 진행되고 있다. 본 논문에서는 주어지는 다시점 컬러 영상과 깊이 영상의 정보를 동시에 이용하여 다시점 영상 부호화의 효율을 높이는데 그 목적이 있다. 이를 위해 시점 생성 기법을 통해 다시점 영상의 부호화 시 참조하는 주변 시점의 영상들로부터 계산되는 변이 벡터 정보를 줄이는 방법을 제안한다. 실험 결과, 기존의 다시점 비디오 부호화에 비해서 약 0.5~1.5 dB정도의 화질 개선이 이뤄졌고, 평균 17.5%의 비트율 감소를 보였다.

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Efficient De-quantization Method based on Quantized Coefficients Distribution for Multi-view Video Coding (다시점 영상 부호화 효율 향상을 위한 양자화 계수 분포 기반의 효율적 역양자화 기법)

  • Park, Seung-Wook;Jeon, Byeong-Moon
    • Journal of Broadcast Engineering
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    • v.11 no.4 s.33
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    • pp.386-395
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    • 2006
  • Multi-view video coding technology demands the very high efficient coding technologies, because it has to encode a number of video sequences which are achieved from a number of video cameras. For this purpose, multi-view video coding introduces the inter-view prediction scheme between different views, but it shows a limitation of coding performance enhancement by adopting only new prediction method. Accordingly, we are going to achieve the more coding performance by enhancing dequantizer perfermance. Multi-view video coding is implemented basically based on H.264/AVC and uses the same quantization/de-quantization method as H.264/AVC does. The conventional quantizer and dequantizer is designed with the assumption that input residual signal follows the Laplacian PDF. However, it doesn't follow the fixed PDF type always. This mismatch between assumption and real data causes degradation of coding performance. To solve this problem, we propose the efficient de-quantization method based on quantized coefficients distribution at decoder without extra information. The extensive simulation results show that the proposed algorithm produces maximum $1.5\;dB{\sim}0.6\;dB$ at high bitrate compared with that of conventional method.

Fast Intra Mode Decision Algorithm for Depth Map Coding using Texture Information in 3D-AVC (3D-AVC에서 색상 영상 정보를 이용한 깊이 영상의 빠른 화면 내 예측 모드 결정 기법)

  • Kang, Jinmi;Chung, Kidong
    • Journal of Korea Multimedia Society
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    • v.18 no.2
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    • pp.149-157
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    • 2015
  • The 3D-AVC standard aims at improving coding efficiency by applying new techniques for utilizing intra, inter and view predictions. 3D video scenes are rendered with existing texture video and additional depth map. The depth map comes at the expense of increased computational complexity of the encoding process. For real-time applications, reducing the complexity of 3D-AVC is very important. In this paper, we present a fast intra mode decision algorithm to reduce the complexity burden in the 3D video system. The proposed algorithm uses similarity between texture video and depth map. The best intra prediction mode of the depth map is similar to that of the corresponding texture video. The early decision algorithm can be made on the intra prediction of depth map coding by using the coded intra mode of texture video. Adaptive threshold for early termination is also proposed. Experimental results show that the proposed algorithm saves the encoding time on average 29.7% without any significant loss in terms of the bit rate or PSNR value.

An efficient inter-sub block filtering for BVSP in 3D-HEVC (3D-HEVC 에서 효율적인 BVSP 를 위한 서브 블록간 필터링 방법)

  • Lee, Jae Yung;Han, Jong Ki
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2013.06a
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    • pp.351-353
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    • 2013
  • 본 논문에서는 현재 활발하게 표준화가 진행중인 3D-HEVC 의 기술들 중 Backward View Synthesis Prediction(BVSP)에서 움직임 보상을 수행하는 서브 블록 경계에 가우시안 필터를 적용하는 방법을 제안한다. BVSP 에서는 4x4 서브 블록 단위로 대표 깊이 정보를 구하여 움직임 보상을 수행하기 때문에 서브 블록 경계에 블록킹 왜곡이 발생할 수 있으므로 가우시안 필터를 통해 이러한 왜곡을 줄일 수 있다. 하지만 모든 경계 픽셀에 대해 가우시안 필터를 적용하지 않고 경계 픽셀의 주변 정보에 따라 적응적으로 가우시안 필터를 적용하고, 필터의 컨트롤 파라미터 또한 적응적으로 변경하는 방법을 제시한다. 제안하는 방법을 기존의 HTM 6.2 와 비교했을 때, 평균 0.1%의 부호화 효율 개선을 보이고 복잡도는 1.2% 증가 하였다.

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Ultra-mode Decision Algorithm for Fast Encoding of H.264/AVC Video (H.264/AVC비디오의 고속 부호화를 위한 인트라모드 선택 알고리듬)

  • Kim, Dong-Hyung;Jeong, Je-Chang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.6C
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    • pp.585-593
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    • 2007
  • For the improvement of coding efficiency, the H.264 standard uses new coding tools such as VBS, 1/4-pel accurate ME, multiple references, intra prediction, loop filter, etc. Using these coding tools, H.264 has achieved significant improvements from rate-distortion point of view compared to existing standards. However, the encoder complexity is greatly increased due to these coding tools. We focus on the complexity reduction method of intra-mode decision. Our algorithm first restricts selective prediction modes of Intra4x4 using a simple preprocessing. The prediction modes of Intra4x4 are used for restricting those of the other inter-modes. Simulation results show that the proposed method outperforms other conventional methods and save about 82% of total encoding time.

Adaptive Pre-/Post-Filters for NRT-Based Stereoscopic Video Coding

  • Lee, Byung-Tak;Lee, BongHo;Choi, Haechul;Kim, Jin-Soo;Yun, Kugjin;Cheong, Won-Sik;Kim, Jae-Gon
    • ETRI Journal
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    • v.34 no.5
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    • pp.666-673
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    • 2012
  • Non-real-time delivery of stereoscopic video has been considered as a service scenario for 3DTV to overcome the limited bandwidth in the terrestrial digital television system. A hybrid codec combining MPEG-2 and H.264/AVC has been suggested for the compression of stereoscopic video for 3DTV. In this paper, we propose a stereoscopic video coding scheme using adaptive pre-/post-filters (APPF) to improve the quality of 3D video while retaining compatibility with legacy video coding standards. The APPF are applied adaptively to blocks of various sizes determined by the macroblock coding mode and reference frame index. Experiment results show that the proposed method achieves up to 24.86% bit rate savings relative to a hybrid codec of MPEG-2 and H.264/AVC including the inter-view prediction.

Climatological Variability of Multisatellite-derived Sea Surface Temperature, Sea Ice Concentration, Chlorophyll-a in the Arctic Ocean (북극해에서 다중위성 자료를 이용한 표층수온, 해빙농도 및 클로로필의 장기 변화)

  • Kim, Hyuna;Park, Jinku;Kim, Hyun-Cheol;Son, Young Baek
    • Korean Journal of Remote Sensing
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    • v.33 no.6_1
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    • pp.901-915
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    • 2017
  • Recently, global climate change has caused a catastrophic event in the Arctic Ocean, directly and indirectly. The air-sea interaction has caused the significant sea-ice reduction in the Arctic Ocean, and has been accelerating the Arctic warming. Many scientists are worried about the Arctic environment change, suggesting that many of anomalous events will produce direct or indirect biophysical effects on the Arctic. The aim of this study is to understand the inter-annual variability of the Arctic Ocean in wide-view using multi-satellite-derived measurements. Sea surface temperature (SST) and sea ice concentration (SIC) data were obtained from Optimum Interpolation Sea Surface Temperature (OISST) and ECMWF ERA-Interim, respectively. Chlorophyll-a concentration (CHL) was obtained from Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) and Aqua sensor from MODerate resolution Imaging Spectroradiometer (MODIS-Aqua) sensor which has continuously observed since 1998. From 1998 to 2016 summer in the Arctic Ocean which was defined as regions over $60^{\circ}N$ in this study, there were three consequences that CHL increase ($0.15mg\;m^{-3}\;decade^{-1}$), SST warming ($0.43^{\circ}C\;decade^{-1}$) and SIC decrease ($-5.37%\;decade^{-1}$). While SST and SIC highly correlated each other (r = -0.76), a relationship between CHL and SIC was very low ($r={\pm}0.1$) because of data limitations. And a relationship between CHL and SST shows meaningful results ($r={\pm}0.66$) with regional differences.

A Study on Intelligent Value Chain Network System based on Firms' Information (기업정보 기반 지능형 밸류체인 네트워크 시스템에 관한 연구)

  • Sung, Tae-Eung;Kim, Kang-Hoe;Moon, Young-Su;Lee, Ho-Shin
    • Journal of Intelligence and Information Systems
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    • v.24 no.3
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    • pp.67-88
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    • 2018
  • Until recently, as we recognize the significance of sustainable growth and competitiveness of small-and-medium sized enterprises (SMEs), governmental support for tangible resources such as R&D, manpower, funds, etc. has been mainly provided. However, it is also true that the inefficiency of support systems such as underestimated or redundant support has been raised because there exist conflicting policies in terms of appropriateness, effectiveness and efficiency of business support. From the perspective of the government or a company, we believe that due to limited resources of SMEs technology development and capacity enhancement through collaboration with external sources is the basis for creating competitive advantage for companies, and also emphasize value creation activities for it. This is why value chain network analysis is necessary in order to analyze inter-company deal relationships from a series of value chains and visualize results through establishing knowledge ecosystems at the corporate level. There exist Technology Opportunity Discovery (TOD) system that provides information on relevant products or technology status of companies with patents through retrievals over patent, product, or company name, CRETOP and KISLINE which both allow to view company (financial) information and credit information, but there exists no online system that provides a list of similar (competitive) companies based on the analysis of value chain network or information on potential clients or demanders that can have business deals in future. Therefore, we focus on the "Value Chain Network System (VCNS)", a support partner for planning the corporate business strategy developed and managed by KISTI, and investigate the types of embedded network-based analysis modules, databases (D/Bs) to support them, and how to utilize the system efficiently. Further we explore the function of network visualization in intelligent value chain analysis system which becomes the core information to understand industrial structure ystem and to develop a company's new product development. In order for a company to have the competitive superiority over other companies, it is necessary to identify who are the competitors with patents or products currently being produced, and searching for similar companies or competitors by each type of industry is the key to securing competitiveness in the commercialization of the target company. In addition, transaction information, which becomes business activity between companies, plays an important role in providing information regarding potential customers when both parties enter similar fields together. Identifying a competitor at the enterprise or industry level by using a network map based on such inter-company sales information can be implemented as a core module of value chain analysis. The Value Chain Network System (VCNS) combines the concepts of value chain and industrial structure analysis with corporate information simply collected to date, so that it can grasp not only the market competition situation of individual companies but also the value chain relationship of a specific industry. Especially, it can be useful as an information analysis tool at the corporate level such as identification of industry structure, identification of competitor trends, analysis of competitors, locating suppliers (sellers) and demanders (buyers), industry trends by item, finding promising items, finding new entrants, finding core companies and items by value chain, and recognizing the patents with corresponding companies, etc. In addition, based on the objectivity and reliability of the analysis results from transaction deals information and financial data, it is expected that value chain network system will be utilized for various purposes such as information support for business evaluation, R&D decision support and mid-term or short-term demand forecasting, in particular to more than 15,000 member companies in Korea, employees in R&D service sectors government-funded research institutes and public organizations. In order to strengthen business competitiveness of companies, technology, patent and market information have been provided so far mainly by government agencies and private research-and-development service companies. This service has been presented in frames of patent analysis (mainly for rating, quantitative analysis) or market analysis (for market prediction and demand forecasting based on market reports). However, there was a limitation to solving the lack of information, which is one of the difficulties that firms in Korea often face in the stage of commercialization. In particular, it is much more difficult to obtain information about competitors and potential candidates. In this study, the real-time value chain analysis and visualization service module based on the proposed network map and the data in hands is compared with the expected market share, estimated sales volume, contact information (which implies potential suppliers for raw material / parts, and potential demanders for complete products / modules). In future research, we intend to carry out the in-depth research for further investigating the indices of competitive factors through participation of research subjects and newly developing competitive indices for competitors or substitute items, and to additively promoting with data mining techniques and algorithms for improving the performance of VCNS.