共查询到19条相似文献,搜索用时 140 毫秒
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多视点视频编码除应具有较高的编码效率外,还应该包括后向兼容性、时间随机访问和视点可分级性等,这些都主要取决于所采用的预测结构。目前所提供的多视点视频编码(Joint Multi-view Video Coding, JMVC)采用固定的视点间预测结构,难以适应复杂情况的多视点视频编码。该文综合考虑编码效率和用户随机访问等因素,根据多视点视频相关性分析自适应调整视点间预测结构,以获得较好的编码综合性能。试验结果表明,与JMVC相比,该文的方法在提高编码效率的同时,有较好的随机访问性能。 相似文献
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应用于多视点视频压缩的多参考B帧快速编码算法 总被引:2,自引:0,他引:2
基于H.264平台就多视点视频压缩中多参考帧技术存在计算复杂度高的现状,根据多视点视频序列特性,提出了一种针对多参考B帧的快速多视点视频编码压缩算法。新算法改进了多参考帧列表策略,并结合多视点视频序列的时空域相关性特性,提出了适用于多视点视频编码的参考帧列表调整策略。此外,还针对多种块模式编码引入了块模式预判策略。新算法在保证率失真性能的基础上,有效地降低了计算复杂度,提高了多视点视频编码速度。虽然本文是基于M-Picture编码结构实现了新算法,但它同样适用于其它应用多参考B帧预测技术的多视点视频编码结构中。 相似文献
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Side-by-Side(SbS)是立体视频常用的格式。传统的视频编码方法利用帧内预测或帧间预测对视频进行压缩编码。基于H.264视频压缩编码标准,针对SbS格式的立体视频提出了一种基于多参考帧方式的视间预测编码方法,并在JM测试代码基础上将其实现。实验结果表明,加入视间预测编码后,以很小的PSNR损失为代价,使得SbS视频的压缩效率提高了大约10%~20%。 相似文献
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Side-by-Side(SbS)是立体视频常用的格式。传统的视频编码方法利用帧内预测或帧间预测对视频进行压缩编码。本文基于H.264视频压缩编码标准,针对SbS格式的立体视频提出了一种基于多参考帧方式的视间预测编码方法,并在JM测试代码基础上将其实现。实验结果表明,加入视间预测编码后,以很小的PSNR损失为代价,使得SbS视频的压缩效率提高了大约10%至20%。 相似文献
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预测结构是多视点视频编码(Multi-View Video Coding,MVC)研究的主要内容之一。MVC目前采用HHI(Heinrich-Hertz-Institute)提出的分层次B帧预测结构(HBP),比联播预测结构获得了更好的压缩效率。分析了多种预测结构,并针对平行摄像机采集的多视点视频序列,提出了一种新的预测结构AS_EIPP,该结构充分利用相邻视点间的相关性和多参考帧模式,进一步提高了压缩效率。在多视点视频软件测试平台JMVC8.3上进行验证,实验结果表明:新的预测结构在保证重建视频质量基本不变的前提下,压缩效率比HBP预测结构提高了1%~4%。 相似文献
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在当今这个数据爆炸增长的时代,深度学习强大的非线性建模能力进一步提高了多视点视频编码的率失真性能.对此,介绍多视点视频的特点及应用,重点对深度学习背景下现有的多视点视频编码方法进行介绍和总结,并展望多视点视频编码未来的发展趋势,旨在进一步发挥深度学习的能力,为用户提供更佳的观看体验. 相似文献
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首先分析了JMVC的参考预测结构,利用1个Go P(Group of Picture)中不同时间层上的帧与其参考帧之间的相关度不同和不同时间层上的帧数目也不同的特点,提出了去除奇数视点最高和次高时间层的视点间预测,并增加偶数视点非关键帧的最低和次低时间层的视点间预测的预测结构。实验结果表明,提出的预测结构基本不影响视频质量,且表现出了更加出色的编码效率,编码的复杂度减少幅度高达15%,输出码率也有所减少,较好地改善了编码的实时性能。 相似文献
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多视点视频编码(Muti-view Video Coding,MVC)标准采用预测关系固定的编码结构,不能根据视频序列调整预测关系,导致无法获得更好的编码效率.本文针对这一缺陷提出一种确定预测结构的方法,首先对图像进行下采样获得粗粒度图像,然后利用粗粒度图像间的灰度方差获得灰度相近的视点,最后对所选取的灰度相近的视点运用全局视差确定I-视点.经实验验证,本文的方法可以提高编码效率并减少编码中的缓存容量. 相似文献
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This paper proposes a novel light field image compression approach with viewpoint scalability and random access functionalities. Although current state-of-the-art image coding algorithms for light fields already achieve high compression ratios, there is a lack of support for such functionalities, which are important for ensuring compatibility with different displays/capturing devices, enhanced user interaction and low decoding delay. The proposed solution enables various encoding profiles with different flexible viewpoint scalability and random access capabilities, depending on the application scenario. When compared to other state-of-the-art methods, the proposed approach consistently presents higher bitrate savings (44% on average), namely when compared to pseudo-video sequence coding approach based on HEVC. Moreover, the proposed scalable codec also outperforms MuLE and WaSP verification models, achieving average bitrate saving gains of 37% and 47%, respectively. The various flexible encoding profiles proposed add fine control to the image prediction dependencies, which allow to exploit the tradeoff between coding efficiency and the viewpoint random access, consequently, decreasing the maximum random access penalties that range from 0.60 to 0.15, for lenslet and HDCA light fields. 相似文献
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In this paper, we propose an adaptive multiview video coding scheme based on spatiotemporal correlation analyses using hierarchical B picture (AMVC‐HBP) for the integrative encoding performances, including high compression efficiency, low complexity, fast random access, and view scalability, by integrating multiple prediction structures. We also propose an in‐coding mode‐switching algorithm that enables AMVC‐HBP to adaptively select a better prediction structure in the encoding process without any additional complexity. Experimental results show that AMVC‐HBP outperforms the previous multiview video coding scheme based on H.264/MPEG‐4 AVC using the hierarchical B picture (MVC‐HBP) on low complexity for 21.5%, on fast random access for about 20%, and on view scalability for 11% to 15% on average. In addition, distinct coding gain can be achieved by AMVC‐HBP for dense and fast‐moving sequences compared with MVC‐HBP. 相似文献
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Tsz-Kwan Lee Yui-Lam Chan Wan-Chi Siu 《Journal of Visual Communication and Image Representation》2013,24(8):1243-1251
Low-delay hierarchical prediction structure is currently adopted in various new video coding standards. The only hurdle of this structure is the need of motion estimation in distant reference frames. To maintain high coding efficiency, a large search range for motion estimation can improve the coding efficiency in distant reference pictures. Computational complexity will thus be increased dramatically. In this paper, a fast motion estimation scheme for a low-delay hierarchical P-frame structure is proposed. The proposed scheme adopts a motion vector composition strategy to expedite the motion estimation process for distant reference frames in the hierarchical P structure. In addition, a motion vector composition algorithm is tailor-made with the proposed hierarchical P coding scheme to further improve the coding efficiency. Simulation results show that the proposed scheme can deliver a remarkable complexity savings and coding efficiency improvement on coding a frame in low temporal layers of the hierarchical P structure. 相似文献
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为了实现高清、超高清视频实时编码通信传输, 针对高效视频编码(HEVC)帧间编码计算复杂度过高的问题,根据图像的文理复杂度和 编码单元的零块统计特征,提出一种新的HEVC快速帧间模式判决算法。根据Merge模式下 整单元一分为四的4个子编码单元纹 理相似度确定是否提前终止编码单元(CU)划分,同时利用帧间2N×2N预测模式下零系数与非零系数分布的区域统计特征,选择符合零块分 布特征的最佳预测单元(PU)模式。实验结果表明,在低延迟B(LDB,low-delay B)和随机访 问(RA,random access)配置条件下,提出的算法在保持编码 性能基本不变的情况下,HEVC帧间预测编码时间分别平均减少了60.2%与59.4%。 相似文献
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Xinpeng Huang Qiuwen Zhang Xiaoxin Zhao Weiwei Zhang Yan Zhang Yong Gan 《Signal, Image and Video Processing》2017,11(1):33-40
The high efficiency video coding (HEVC) is superior to the previous video coding standards in compression performance, while the computational complexity is introduced simultaneously. The complexity increases mainly due to the novel flexible partitioning scheme that allows the inter-prediction mode partition split via exhaustive rate-distortion optimization (RDO). In this paper, a fast inter-prediction mode decision algorithm is proposed, which contains adaptive threshold determination based on quantization parameter and fast inter-prediction mode partition decision. The proposed algorithm utilizes the edge information of the partition to simplify the RDO and then accelerates coding time of inter-prediction mode decision structure for the original HEVC encoder. The experimental results show that the proposed algorithm can achieve 39.5 % coding time reduction with just 1.97 % bitrate increase on average under random access condition and 35.2 % coding time reduction with just 1.89 % bitrate increase on average under low-delay B condition, compared to the original HEVC encoder. 相似文献
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Techniques are introduced to solve two problems caused by the wide bandwidth of HDTV signals. One problem is that HDTV signals have more random noise than conventional TV signals, which causes coding efficiency degradation. The other is that very high sampling frequencies are required, which restricts the hardware implementation of the coding algorithm. To solve the first problem, it is proposed to use a spatio-temporal adaptive filter that can reduce random noise and improve coding efficiency. With regard to the second problem, an extrapolative and interpolative coding algorithm with adaptive intrafield/interframe prediction is presented. This algorithm eliminates the problem caused by the high sampling frequencies and provides efficient coding performance. A computer simulation is carried out to estimate the coding performance. Based on the simulation results, experimental coder hardware was implemented for 1125-line/60 Hz HDTV signals in order to evaluate real-time coding performance. The experimental results show that this coding method can provide good picture quality at around 90 or 135 Mb/s, and that HDTV digital transmission is very promising at the broadband ISDN H4 rate 相似文献
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Chia-Yang Tsai Hsueh-Ming Hang 《Journal of Visual Communication and Image Representation》2010,21(8):917-929
A rate-distortion model for describing the motion prediction efficiency in interframe wavelet video coding is proposed in this paper. Different from the non-scalable video coding, the scalable wavelet video coding needs to operate under multiple bitrate conditions and it has an open-loop structure. The conventional Lagrangian multiplier, which is widely used to solve the rate-distortion optimization problems in video coding, does not fit well into the scalable wavelet structure. In order to find the rate-distortion trade-off due to different bits allocated to motion and textual information, we suggest a motion information gain (MIG) metric to measure the motion prediction efficiency. Based on this metric, a new cost function for mode decision is proposed. Compared with the conventional Lagrangian method, our experiments show that the proposed method is less extraction-bitrate dependent and generally improves both the PSNR performance and the visual quality for the scalability cases. 相似文献
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高性能视频编码(HEVC)是刚确立的最新一代的视频编码标准。对于帧内编码,HEVC最大的特点是采用了从64×64至8×8的编码单元划分和35种帧内预测模式,HEVC通过遍历所有的分块和帧内预测模式,选取最优的预测方式,这种帧内预测方式在提高预测精度的同时也大大增加了编码的计算复杂度。为了降低帧内预测的计算复杂度,HM2.0版以上的HEVC测试软件采用一种基于两步预测的快速帧内模式选择算法。在此基础上本文首先提出了一种基于纹理方向的快速粗选方案,减少参与计算的粗选模式数,进而提出基于结构相关的决策方法,利用同质图像区域的纹理相似性,减少参与率失真代价函数计算的候选模式数量,进一步降低了帧内预测计算复杂度。实验结果表明,本文所提出的快速算法,在保持编码质量基本不变的条件下,可以使基于两步预测的快速帧内模式选择时间缩短25%。 相似文献