Automatic, robust global motion estimation using clustering

Global motion estimation (GME) is a vital part of many video compression and computer vision applications. However, the large moving foreground objects that are present in many video scenes make the task of GME more challenging. In this paper, we propose an automatic, efficient, and robust approach for GME that addresses the issue of large foreground objects. The proposed GME algorithm is based on two key ideas: a new clustering technique, to automate the initial segmentation of background and foreground blocks, and a modified Lorentzian estimator, to reduce the impact of any remaining foreground blocks on the GME process. We also apply an up-sampling technique to the estimated motion parameters to remove any errors caused by under-sampling during the warping process. These ideas provide a significant improvement in performance when combined into a common framework. Simulation results and analyses demonstrate the improved performance of our proposed algorithm over other state-of-the-art methods.     

A novel compact circuit for 4-PAM energy-efficient high speed interconnect data transmission and reception

Transmission of signals, whether on-chip or off-chip, places severe constraints on timing and extracts a large price in energy. New silicon device technologies, such as back-plane CMOS, provide a programmable and adaptable threshold voltage as an additional tool that can be used for low power design. We show that one particularly desirable use of this freedom is energy-efficient high-speed transmission across long interconnects using multi-valued encoding. Our multi-valued CMOS circuits take advantage of the threshold voltage control of the transistors, by using the signal-voltage-to-threshold-voltage span, in order to make area-efficient implementations of 4-PAM (pulse amplitude modulation) transceivers operating at high speed. In a comparison of a variety of published technologies, for signal transmission with interconnects of 10-15 mm length, we show up to 50% improvement in energy for on-chip signal transmission over binary encoding together with higher limits for operating speeds without a penalty in circuit noise margin.     

Global attention retinex network for low light image enhancement

Most low-light image enhancement methods only adjust the brightness, contrast and noise reduction of low-light images, making it difficult to recover the lost information in darker areas of the image, and even cause color distortion and blurring. To solve the above problems, a global attention-based Retinex network (GARN) for low-light image enhancement is proposed in this paper. We propose a novel global attention module which computes multiple dimensional information in the channel attention module to help facilitate inference learning. Then the global attention module is embedded into different layers of the network to extract richer shallow texture features and deep semantic features. This means that the rich features are more conducive to learning the mapping relationship between low-light images to normal-light images, so that the detail recovery of dark regions is enhanced in low-light images. We also collected a low/normal light image dataset with multiple scenes, in which the images paired as training set can succeed to be applied to low-light image enhancement under different lighting conditions. Experimental results on publicly available datasets show that our method has better effectiveness and generality than the state-of-the-art methods in terms of evaluations metrics such as PSNR, SSIM, NIQE, Entropy.     

一种快速自适应全局运动估计算法的研究

该文提出一种快速自适应全局运动估计算法。该方法从分析块匹配运动矢量统计特性出发,通过 引入一个可预设置参数,计算当前帧与参考帧之间的基本平移矢量,并自适应地采取混合全局运动、局部运 动估计的算法处理不同特征的源数据.仿真结果表明,与传统方法相比,该文算法复杂性低、处理延时小、 更利于硬件实现,在PSNR变化不大的情况下,编码效率有较大的改善.     

提高H.26L压缩视频抗误码性能的全局率失真优化方法

该文从较新的H.26L视频压缩编码标准出发,并结合Internet信道的Bernoulli和Gilbert 的包丢失模型,提出了一种全局率失真优化的编码模式判决方法,使编码的视频流具有更强的错误恢复能力。实验证明,在实际的Internet信道误码环境下,此方法具有更强的抗错误和实用性,得到了较好的效果。     

国防信息基础设施的建设与管理

讨论了国防信息基础设施的概念,分析了美军国防信息基础设施的发展状况、实施方法、主要途径,提出了发展我军信息基础设施的技术途径和措施建议.     

ATTITUDE RATE ESTIMATION BY GPS DOPPLER SIGNAL PROCESSING

A method is presented for near-Earth spacecraft or aviation vehicle‘s attiude rate cstimation by using relative Doppler frequency shift of the Global Positioning System(GPS)carrier.It comprises two GPS receiving antennas,a signal processing circuit and an algorithm.The whole system is relatvely simple,the cost and weight,as well power consumption,are very low.     

卫星导航系统基四选星算法

随着卫星导航系统的发展,可见星数大大增多,为了减少接收机运算量,需选择可见卫星的一个子类。本文分析了卫星导航系统中N个4星最优分布与某4星最优分布中的k(k≤3)个卫星(共4N+k颗卫星)的联合分布GDOP值,并以此为基础提出了一类低复杂度近似最优的基四选星算法。该算法以经典的4星选择算法(最大体积法和四步选择法)为基础,通过多次迭代与部分执行,实现任意多于4星的卫星选择。仿真结果表明该算法与准优算法相比运算复杂度和GDOP值都更低。     

基于全局背景与特征降维的视觉跟踪算法

相关滤波算法容易受到形变、运动模糊、相似背景等因素的干扰,导致跟踪任务失败。为了克服以上问题,该文提出一种基于全局背景与特征降维的视觉跟踪算法。该算法首先提取紧邻目标的图像区域作为负样本供分类器学习,以抑制相似背景的干扰;然后提出一种基于主成分分析的更新策略,构建降维矩阵压缩HOG特征的维度,在更新分类器的同时减少其冗余度;最后加入颜色特征表征运动目标,并根据特征对系统状态的响应强度进行自适应融合。在标准数据集上将该文提出的算法与Staple, KCF等其他算法进行了仿真对比,结果表明该文算法具有更强的鲁棒性,在形变因素的影响下,所提出的算法与Staple和KCF算法相比距离精度分别提升8.3%和13.1%。     

具有轴突信号传输延迟的双向联想记忆神经网络

双向联想记忆模型是两层异联想网络,本文重点讨论了具有轴突信号传输延迟的双向联想记忆神经网络平衡点存在的条件以及全局稳定性.并用具体例子验证了结论的正确性。本文所讨论的方法具有普遍性,所得到的结果对于网络的设计和应用具有重要的指导意义。