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Fast Macroblock Mode Selection Algorithm for Multiview Video Coding  [cached]
Zongju Peng,Gangyi Jiang,Mei Yu,Qionghai Dai
EURASIP Journal on Image and Video Processing , 2009, DOI: 10.1155/2008/393727
Abstract: Multiview video coding (MVC) plays an important role in three-dimensional video applications. Joint Video Team developed a joint multiview video model (JMVM) in which full-search algorithm is employed in macroblock mode selection to provide the best rate distortion performance for MVC. However, it results in a considerable increase in encoding complexity. We propose a hybrid fast macroblock mode selection algorithm after analyzing the full-search algorithm of JMVM. For nonanchor frames of the base view, the proposed algorithm halfway stops the macroblock mode search process by designing three dynamic thresholds. When nonanchor frames of the other views are being encoded, the macroblock modes can be predicted from the frames of the neighboring views due to the strong correlations of the macroblock modes. Experimental results show that the proposed hybrid fast macroblock mode selection algorithm promotes the encoding speed by 2.37 ¢ € ‰ ¢ ¢ € ‰9.97 times without noticeable quality degradation compared with the JMVM.
Fast Macroblock Mode Selection Algorithm for Multiview Video Coding  [cached]
Peng Zongju,Jiang Gangyi,Yu Mei,Dai Qionghai
EURASIP Journal on Image and Video Processing , 2008,
Abstract: Multiview video coding (MVC) plays an important role in three-dimensional video applications. Joint Video Team developed a joint multiview video model (JMVM) in which full-search algorithm is employed in macroblock mode selection to provide the best rate distortion performance for MVC. However, it results in a considerable increase in encoding complexity. We propose a hybrid fast macroblock mode selection algorithm after analyzing the full-search algorithm of JMVM. For nonanchor frames of the base view, the proposed algorithm halfway stops the macroblock mode search process by designing three dynamic thresholds. When nonanchor frames of the other views are being encoded, the macroblock modes can be predicted from the frames of the neighboring views due to the strong correlations of the macroblock modes. Experimental results show that the proposed hybrid fast macroblock mode selection algorithm promotes the encoding speed by 2.37 9.97 times without noticeable quality degradation compared with the JMVM.
Novel Side Information Generation Algorithm of Multiview Distributed Video Coding for Multimedia Sensor Networks  [PDF]
Fu Xiao,Jinkai Liu,Jian Guo,Linfeng Liu
International Journal of Distributed Sensor Networks , 2012, DOI: 10.1155/2012/582403
Abstract: The traditional multiview distributed video coding scheme using regional unified coding may lead to distortion problem of decoding estimation of the intense motion region. This paper presents a novel multiview distributed video coding algorithm. In the main perspective, gaining the intense motion regions of Wyner-Ziv frame according to the criteria of ROI, the algorithm extracts their DCT low-frequency coefficients for the entropy coding, in order to generate the best temporal side information. For the nonintense motion regions, the algorithm utilizes motion compensation interpolation (MCI) to generate side information. Finally, side information based on fusion of temporal and spatial side information will be gained. Experimental results show that our proposed algorithm can gain more accurate motion estimation in the intense motion region. Quality of decoded image is improved with the same transmit rate; thus, energy consumption of sensor nodes will be decreased ultimately. 1. Introduction In recent years, along with the rapid development of the wireless multimedia communication technology [1], digital video requirements are being increased. People would like to see natural characterization of objects clearer and more realistic: the traditional single-view video network can only provide two-dimensional visual, and three-dimensional visual senses cannot be provided better; so the multiview video network appears. In the multiview video network, which has the limits of low power, storage capacity, computational and communication ability,?? it does not only need low-complexity encoding, but also??requires real-time video encoding and transmission. Traditional video coding standards, such as MPEG-x or H.26x, mainly rely on the hybrid architecture, encoder using motion estimation to fully exploit the video sequences of time, and spatial correlation information. Since the heavy computing burden of the motion estimation and compensation task in these video compression standards, the encoder is 5 to 10 times more complex than the decoder [2, 3]. Traditional video coding system is not suitable, novel coding methods are required. Wide attention has been focused on new video codec framework, distributed video coding (DVC) from scholars, which uses intraframe encoding and interframe decoding. Decoder explores the correlation of video signals for interframe prediction decoding; so DVC removes the complexity of the interframe prediction coding in encoder. Distributed Video Coding, which has the characteristics of low-complexity encoding and good robustness, can meet
An Efficient Fractal Video Sequences Codec with Multiviews  [PDF]
Shiping Zhu,Liyun Li,Juqiang Chen,Kamel Belloulata
Mathematical Problems in Engineering , 2013, DOI: 10.1155/2013/853283
Abstract: Multiview video consists of multiple views of the same scene. They require enormous amount of data to achieve high image quality, which makes it indispensable to compress multiview video. Therefore, data compression is a major issue for multiviews. In this paper, we explore an efficient fractal video codec to compress multiviews. The proposed scheme first compresses a view-dependent geometry of the base view using fractal video encoder with homogeneous region condition. With the extended fractional pel motion estimation algorithm and fast disparity estimation algorithm, it then generates prediction images of other views. The prediction image uses the image-based rendering techniques based on the decoded video. And the residual signals are obtained by the prediction image and the original image. Finally, it encodes residual signals by the fractal video encoder. The idea is also to exploit the statistical dependencies from both temporal and interview reference pictures for motion compensated prediction. Experimental results show that the proposed algorithm is consistently better than JMVC8.5, with 62.25% bit rate decrease and 0.37?dB PSNR increase based on the Bjontegaard metric, and the total encoding time (TET) of the proposed algorithm is reduced by 92%. 1. Introduction There are several image/video compression methods, for example, JPEG, MPEG, and H.26X, which are all based on motion estimation/compensation (ME/MC) [1]. But fractal compression, which is based on the IFS (iterated function system) proposed by Mandelbrot [2], is a new approach to image coding. After Jacquin [3] proposed the first automatic algorithm for fractal coding of still images, much effort has been made in the area of the fractal still image coding techniques. For example, Fisher made use of quadtree to improve the method [4]. With the development of the fractal image compression, fractal coding method has been applied to video sequence compression [5]. Wang and Lai proposed a hybrid compression algorithm [6], which merged the advantages of a cube-based fractal compression method and a frame-based fractal compression method. And an adaptive partition instead of fixed-size partition was discussed. The adaptive partition and the hybrid compression algorithm exhibit relatively high compression ratio for the sequence of motion images from a videoconference. But the computational complexity is high. And with the advantages of high compression ratio and resolution-independent in the fractal coding, more researches were conducted. Distasi et al. tried to overcome the difficulty of such
Iterative Multiview Side Information for Enhanced Reconstruction in Distributed Video Coding  [cached]
Ouaret Mourad,Dufaux Frédéric,Ebrahimi Touradj
EURASIP Journal on Image and Video Processing , 2009,
Abstract: Distributed video coding (DVC) is a new paradigm for video compression based on the information theoretical results of Slepian and Wolf (SW) and Wyner and Ziv (WZ). DVC entails low-complexity encoders as well as separate encoding of correlated video sources. This is particularly attractive for multiview camera systems in video surveillance and camera sensor network applications, where low complexity is required at the encoder. In addition, the separate encoding of the sources implies no communication between the cameras in a practical scenario. This is an advantage since communication is time and power consuming and requires complex networking. In this work, different intercamera estimation techniques for side information (SI) generation are explored and compared in terms of estimating quality, complexity, and rate distortion (RD) performance. Further, a technique called iterative multiview side information (IMSI) is introduced, where the final SI is used in an iterative reconstruction process. The simulation results show that IMSI significantly improves the RD performance for video with significant motion and activity. Furthermore, DVC outperforms AVC/H.264 Intra for video with average and low motion but it is still inferior to the Inter No Motion and Inter Motion modes.
Iterative Multiview Side Information for Enhanced Reconstruction in Distributed Video Coding  [cached]
Mourad Ouaret,Frédéric Dufaux,Touradj Ebrahimi
EURASIP Journal on Image and Video Processing , 2009, DOI: 10.1155/2009/591915
Abstract: Distributed video coding (DVC) is a new paradigm for video compression based on the information theoretical results of Slepian and Wolf (SW) and Wyner and Ziv (WZ). DVC entails low-complexity encoders as well as separate encoding of correlated video sources. This is particularly attractive for multiview camera systems in video surveillance and camera sensor network applications, where low complexity is required at the encoder. In addition, the separate encoding of the sources implies no communication between the cameras in a practical scenario. This is an advantage since communication is time and power consuming and requires complex networking. In this work, different intercamera estimation techniques for side information (SI) generation are explored and compared in terms of estimating quality, complexity, and rate distortion (RD) performance. Further, a technique called iterative multiview side information (IMSI) is introduced, where the final SI is used in an iterative reconstruction process. The simulation results show that IMSI significantly improves the RD performance for video with significant motion and activity. Furthermore, DVC outperforms AVC/H.264 Intra for video with average and low motion but it is still inferior to the Inter No Motion and Inter Motion modes.
Multiview Video Coding Scheme Based on Disparity Estimation Algorithm
基于视差估计算法的多视点视频预测方案

PAN Feng,MA Li-ni,DU Xiao-yu,
潘峰
,马力妮,杜小钰

计算机科学 , 2008,
Abstract: Multiview video coding is a key technology of stereo video,and disparity estimation is the most popular algorithm of current multiview video coding schemes.The theory of disparity estimation algorithm is first investigated,and several typical coding techniques are analyzed in detail.Then a novel multiview coding scheme is proposed which is based on hierarchical B pictures and correlation property of viewpoints.Experimental results show that the proposed scheme is efficient.
Fast Algorithms for Inter-view Prediction of Multiview Video Coding  [cached]
Rong Pan,Zheng-Xin Hou,Yu Liu
Journal of Multimedia , 2011, DOI: 10.4304/jmm.6.2.191-201
Abstract: The compression efficiency and complexity should be simultaneously taken into consideration in Multiview Video Coding (MVC). In order to reduce the complexity while maintaining the efficiency of MVC, we proposed in this paper two algorithms called Adaptive Search Region Adjustment (ASRA) and Adaptive Selection of Inter-view References (ASIR). In ASRA, we simplified the exiting method to obtain the global disparity vector (GDV), using which the correlations between the disparity vector (DV) and predicted vector were exploited. The statistical property of the absolute difference value of $DV$ and GDV was analyzed and the results were applied to adjust the search range dynamically. In ASIR, we first used the prediction information of the lower temporal layer in the hierarchical B picture prediction structure to reduce the number of inter-view reference pictures, and then applied the results of reference selection after inter_16×16 prediction mode decision to revise our method. The experimental results demonstrate that the algorithms suggested in this paper can reduce the computation up to 25% with little decrease of compression efficiency.
A Poisson Hidden Markov Model for Multiview Video Traffic  [PDF]
Lorenzo Rossi,Jacob Chakareski,Pascal Frossard,Stefania Colonnese
Computer Science , 2013,
Abstract: Multiview video has recently emerged as a means to improve user experience in novel multimedia services. We propose a new stochastic model to characterize the traffic generated by a Multiview Video Coding (MVC) variable bit rate source. To this aim, we resort to a Poisson Hidden Markov Model (P-HMM), in which the first (hidden) layer represents the evolution of the video activity and the second layer represents the frame sizes of the multiple encoded views. We propose a method for estimating the model parameters in long MVC sequences. We then present extensive numerical simulations assessing the model's ability to produce traffic with realistic characteristics for a general class of MVC sequences. We then extend our framework to network applications where we show that our model is able to accurately describe the sender and receiver buffers behavior in MVC transmission. Finally, we derive a model of user behavior for interactive view selection, which, in conjunction with our traffic model, is able to accurately predict actual network load in interactive multiview services.
Fast Mode Decision Algorithm for Inter-Frame Coding in H.264/AVC Extended Scalable Video Coding
Byung-Gyu Kim,Gwang-Soo Hong,Ki-Wook Rim
International Journal of Soft Computing , 2012, DOI: 10.3923/ijscomp.2011.102.110
Abstract: Scalable Video Coding (SVC) is the finalized standard as an extension of H.264/AVC to provide stable multimedia services to various service environment and end-systems. Usually an exhaustive block mode search has been employed to determine the best coding mode for each Macroblock (MB). This gives a high coding efficiency, however it causes very high computational complexity in encoding system. To reduce this complexity of the exhaustive mode search, researchers propose a fast mode determination algorithm for inter-frame coding based on correlative information between base layer and enhancement layers for providing spatial scalability with Medium Grain Signal to noise ratio (MGS) layer. In the proposed algorithm, researchers use Rate-Distortion (RD) costs of BLS (Base Layer Skip) and 16x16 modes and mode information of a corresponding block of the base layer to finish inter-mode search procedure early in the neighboring enhancement layer. Also, an adaptive thresholding scheme is designed. Researchers verify that the overall encoding time can be reduced up to 66.5% based on comparative analysis of experimental results with JSVM 9.12 reference software.
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