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基于运动矢量插值的运动补偿算法 总被引:4,自引:1,他引:3
本文首先研究了相关性约束运动估值算法,然后提出了基于运动矢量插值的运动估值算法,实验表明新算法的预测性能明显一比传统块匹配运动估值算法(BMA)好,而且预测图象的主观质量得到显著改善。 相似文献
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亚象素运动估值快速算法 总被引:3,自引:0,他引:3
高精度的匹配和补偿可以减少预测误差,提高视频图像的压缩效果。文中提出了一种亚象素精度视频运动估值的快速算法,根据半象素精度运动估值的中间结果,直接推算出更高精度的运动估值。该算法为高精度亚象素运动估值的研究提供了算法保证。 相似文献
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传统的块匹配运动估值算法(BMA)不适合对下列情形进行运动估计:旋转、伸缩(scale)、形变(deformation)、卷曲(warping)、错切(shear)和不规则的伸展(unevenstretching)等,因而在实际应用中常常出现方块失真、沿运动边缘方向预测性能差等现象。为克服上述缺陷,本文研究了基于多种运动模型的运动估计算法,提出了一种自适应选择运动模型的算法。为了估计模型参数,本文实现了基于模拟退火的运动参数估计算法。实验表明本文算法与传统BMA算法相比较,较好地提高了帧间预测增益。 相似文献
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主要针对模型基编码方案的运动参数估值问题,运用3维运动估值的方法,推导出运用于人脸运动参数估值的运动模型和光流算法,并对该算法的效果进行分析,对算法的改进提出算法。 相似文献
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在分析了现行HDTV运动估值方案的基础上,提出了一种基于快速预测搜索算法的HDTV运动估值方案,其性能优于其它方案。 相似文献
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在介绍模型编码基本原理的基础上,着重介绍了语义基编码,对它的运动估值技术作了详细分析,并用光流法对运动图像进行了运动估值,对该估值算法作了评价和展望。 相似文献
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研究表明采用最小均方误差或绝对误差准则的块匹配运动估值算法对H.261编码器来说不是最好的。本文提出了一种改进的块匹配运动估值算法。它所采用的准则不仅考虑了预测误差能量的大小,还考虑了运动矢量信息以及帧间预测误差的编码比特数目的多少.实验结果表明新的准则能够显著地改善H.261的编码性能。 相似文献
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提出了一种新的多级运动估值器的结构 ,它支持低比特视频编码器的高级预测模式 ,如H.2 63和 MPEG- 4。该 VLSI结构的所有级别中共用一个基本的搜索单元 ( BSU) ,减小了芯片尺寸。另外 ,由于它为计算 8× 8块的绝对误差和 SAD提供了一种对存储器数据流的控制电路 ,因此 ,对于高级预测模式 ,可同时获得 1个宏块运动矢量和每个宏块中的 4个子块运动矢量。这种尺寸较小的运动估值电路可以获得与全搜索块匹配算法 ( FSBMA)相似的编码效果 相似文献
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Xue Xiangyang Wu Lide 《电子科学学刊(英文版)》1998,15(1):22-28
A modified block matching algorithm (BMA) with motion correlation constraint (MCCBMA) is proposed at first. Then a novel motion compensation algorithm (INTPMC) which computes motion vector for each pixel by interpolating motion vectors is presented. In order to increase interframe prediction performance and decrease the computational complexity, an optimizing algorithm for partial motion vectors is described at last. Experimental results show that the proposed algorithm can improve the prediction performance obviously with a moderately increased complexity compared with the conventional full search block matching algorithm (FSBMA). 相似文献
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Majdi Elhaji Abdelkrim Zitouni Samy Meftali Jean-Luc Dekeyser Rached Tourki 《Integration, the VLSI Journal》2013
In the Advanced Video Coding (AVC) standard, motion estimation (ME) adopts many new features to increase the coding performances such as block matching algorithm (BMA), motion vector prediction (MVP) and variable block size motion estimation (VBSME). However, VBSME is utilized in the MPEG4-AVC/H.264 standard which leads to high computational complexity and data dependency that make the hardware implementation very complex. 相似文献
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本文提出了一种运动估计的快速预测搜索算法(PSA)。该算法首先用当前块的三个邻近块运动矢量的线性加权来得到预测矢量,然后以预测点为起始点,采用33的搜索窗进行搜索步长为1的移动窗搜索,直到搜索到达搜索域的边界或搜索的局部最小点位于搜索窗的中心时停止。该算法由于利用了序列图象的实际运动矢量与预测矢量之间距离的空间分布特性一中心偏置分布特性和时间上的相关特性,并采用了中止判决准则,可以明显地减少搜索次数。仿真表明这种算法减少了搜索范围和搜索次数,提高了搜索效率,降低了运动估计的计算复杂性。本文还详细地给出了PSA算法与其它常用快速算法的比较结果。 相似文献
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Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies,a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted,the complexity of motion es timation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Reso lution Motion Estimation (MRME) is improved. 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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一种用于视频编码的块运动估计算法——块特征匹配预测搜索算法 总被引:9,自引:0,他引:9
本文提出了一种块特征匹配预测搜索BFMPS算法,可以用于视频压缩的一些国际标准,如H.261,H.263,MPEG1,MPEG2,HDTV中,BFMPS算法充分利用了序列图像的实际矢量与预测矢量之间距离的空间分布特征,中心偏置分布特性和时间上的相关特性,并采用了中止判决准则,可以明显地减少了运动搜索复杂度,BFMPS算法在匹配运算中采用 简单有交的块特征匹配准则函数,相应的块匹配计算复杂度,数据读 相似文献
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A new method for motion-compensated temporal prediction of image sequences is proposed. Motion vector fields in natural scenes should possess two basic properties. First, the field should be smoothly varying within moving objects to compensate for nonrigid or rotational motion, and scaling of objects. Second, the field should be discontinuous along the boundaries of the objects. In the proposed method the motion vector field is modelled using finite element methods and interpolated using adaptive interpolators to satisfy the above-stated requirements. This is particularly important when only very sparse estimates of motion vector fields are available in the decoder due to bit-rate constraints limiting the amount of overhead information that can be transmitted. The proposed prediction method can be applied for low-bit-rate video coding in conventional codecs based on motion-compensated prediction and transform coding, as well as in model-based codecs. The performance of the proposed method is compared with standard motion-compensated prediction based on block matching. It is shown that for simple video telephony scenes a reduction of more than 30% in the energy of the prediction error can be achieved with an unchanged number of transmitted motion vectors and with only a modest increase in computational complexity. When implemented in an H.261 codec the new prediction method can improve the peak SNR 1–2 dB producing a significant visual improvement. 相似文献