• Title/Summary/Keyword: distributed video coding

Search Result 97, Processing Time 0.029 seconds

Fast Distributed Video Coding using Parallel LDPCA Encoding (LDPCA 병렬 부호화를 이용한 고속 분산비디오부호화)

  • Park, Jongbin;Kim, Jaehwan;Jeon, Byeungwoo
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2010.11a
    • /
    • pp.136-137
    • /
    • 2010
  • 본 논문에서는 고속, 저전력 비디오 부호화에 적합한 변환영역 Wyner-Ziv 분산비디오부호화기를 더욱 고속화하기 위한 병렬처리 방법을 제안한다. 기존에는 변환영역 Wyner-Ziv 분산비디오부호화를 위해 양자화 정보를 비트플레인단위로 분해후 이를 순차적으로 LDPCA 부호화하여 전체 부호화기 연산량에서 LDPCA의 복잡도가 약 54% 정도 차지하였고, 이는 고비트율로 부호화 할수록 더욱 증가하였다. 제안방법은 이를 개선하기 위해 여러 개의 비트플레인을 하나의 심벌 (symbol)로 묶어서 LDPCA 부호화를 수행하여 한 번의 연산으로 여러 개의 데이터를 동시에 처리할 수 있게 한다. 일종의 단일 명령 복수 데이터 처리 (SIMD, Single instruction, multiple data)에 의한 고속화 방법이다. 이를 통해 제안방법은 기존의 순차적 처리 방법에 비해 저비트율에서는 8배, 고비트율에서는 55배까지 LDPCA의 부호화 속도를 향상시켰다. 결과적으로 전체 부호화에서 LDPCA의 상대적인 복잡도 비율은 4%정도로 낮아지게 되었으며 Wyner-Ziv 영상의 부호화 속도도 약 1.5 ~ 2배까지 향상되었다. 제안방법은 LDPCA를 사용하는 다른 Wyner-Ziv 분산비디오부호화 구조에도 적용 가능할 것으로 기대한다.

  • PDF

Side Information Extrapolation Using Motion-aligned Auto Regressive Model for Compressed Sensing based Wyner-Ziv Codec

  • Li, Ran;Gan, Zongliang;Cui, Ziguan;Wu, Minghu;Zhu, Xiuchang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.7 no.2
    • /
    • pp.366-385
    • /
    • 2013
  • In this paper, we propose a compressed sensing (CS) based Wyner-Ziv (WZ) codec using motion-aligned auto regressive model (MAAR) based side information (SI) extrapolation to improve the compression performance of low-delay distributed video coding (DVC). In the CS based WZ codec, the WZ frame is divided into small blocks and CS measurements of each block are acquired at the encoder, and a specific CS reconstruction algorithm is proposed to correct errors in the SI using CS measurements at the decoder. In order to generate high quality SI, a MAAR model is introduced to improve the inaccurate motion field in auto regressive (AR) model, and the Tikhonov regularization on MAAR coefficients and overlapped block based interpolation are performed to reduce block effects and errors from over-fitting. Simulation experiments show that our proposed CS based WZ codec associated with MAAR based SI generation achieves better results compared to other SI extrapolation methods.

Efficient Motion Compensated Interpolation Technique Using Image Resizing (영상의 크기 변환을 이용한 효율적인 움직임 보상 보간 기법)

  • Kwon, Hye-Gyung;Lee, Chang-Woo
    • Journal of Broadcast Engineering
    • /
    • v.18 no.4
    • /
    • pp.599-608
    • /
    • 2013
  • Motion compensated interpolation (MCI) techniques are used for increasing the frame rate and generating the side information in the distributed video coding (DVC) system. In this paper, an efficient MCI technique using the image resizing in the DCT or LiftLT domain is proposed, and the performance of the MCI technique using various sub-pixel generation techniques is analyzed. Extensive computer simulations show that the proposed method produces the superior results compared to the conventional methods.

Performance Comparison of Block-based Distortion Estimations for FRUC Techniques (FRUC 기술을 위한 블록별 왜곡 크기 추정기법의 성능비교)

  • Kim, Jin-Soo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2011.10a
    • /
    • pp.927-929
    • /
    • 2011
  • Since DVC (Distributed Video Coding) and FRUC (Frame Rate Up Conversion) techniques need to have an efficient motion compensated frame interpolation algorithms. Conventional works of these applications have mainly focused on the performance improvement of overall system. But, in some applications, it is necessary to evaluate how well the MCI (Motion Compensated Interpolation) frame matches the original frame. For this aim, this paper deals with the modeling methods for evaluating the block-based matching cost. First, several matching criteria, which have already been dealt with the motion compensated frame interpolation, are introduced and then combined to make estimate models for the size of MSE (Mean Square Error) noise of the MCI frame to original one. Through computer simulations, it is shown that the block-based cost evaluation models are tested and can be effectively used for estimating the MSE noise.

  • PDF

Adaptive Frame Level Rate Control for H.264 (적응적 프레임 레벨 H.264 비트율 제어)

  • Park, Sang-Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.13 no.8
    • /
    • pp.1505-1512
    • /
    • 2009
  • This paper propose a new frame level rate control algorithm for improving video quality and decreasing quality variation of an entire video sequence in a very low bit rate environment. In the proposed scheme, the allocated bits to a GOP are distributed to each frame properly according to the frame characteristics as well as the buffer status and the channel bandwidth. The H.264 standard uses various coding modes and optimization methods to improve the compression performance, which makes it difficult to control the generated traffic accurately. In this paper, proper prediction models for low bit rate environments are lust proposed, and a target distortion is determined using the models. According to the target distortion, the bit budget is allocated to each frame. It is shown by experimental results that the new algorithm can generate the PSNR performance better than that of the existing rate control algorithm.

Block-based Reliability Evaluation Method for FRUC Techniques Using Bi-lateral Symmetrical Motion Estimation (양방향 대칭형 탐색에 기초한 FRUC기법을 위한 블록기반 신뢰성 평가 방법)

  • Park, Se-jeong;Kim, Jin-soo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2012.10a
    • /
    • pp.867-869
    • /
    • 2012
  • FRUC(Frame Rate Up Conversion) is core techniques for higher quality terminals or low channel rate. For these applications, in this paper, we propose a block-based reliability evaluation method for FRUC techniques using bi-lateral symmetrical motion estimation. First, in order to measure the reliability, by introducing cost evaluation tools such as motion vector consistency as well as temporal matching and spatial matching characteristics and then by combining these tools, we propose an efficient method which arrange the blocks according to distortion size. Through several simulations, it is shown that the proposed method is very effective in finding the high distortion blocks. Furthermore, it is expected that the proposed method can be effectively utilized in FRUC techniques and Distributed Video Coding technologies.

  • PDF

Implementation of a Blockchain-based Talent Trading Platform to Reduce Transaction Costs (거래 비용 절감을 위한 블록체인 기반 재능거래 플랫폼)

  • Yang, Seonghun;Jin, Hoe-Yong;Kim, Sang-Kyun
    • Journal of Broadcast Engineering
    • /
    • v.25 no.6
    • /
    • pp.922-934
    • /
    • 2020
  • The talent trading platform is a platform that brokers transactions such as program coding, media content production (video, music, presentation materials, etc.), design, learning, and repair. Existing talent trading platforms provide a server-client model-based service, which incurs server operating costs and arbitration labor costs for transactions, which has a disadvantage that users bear high service fees. This paper proposes a method to reduce server and database operation costs by uploading transaction information to blocks through the system as a distributed app (dApp) based on the Ethereum platform. In addition, it proposes a method to lower transaction fees by reducing the labor cost of transaction arbitrators through smart contracts. Compare and analyze the cost processing procedure and transaction fee size of the blockchain-based talent trading platform and the existing talent trading platform.