图象编码压缩标准H.264中适应码率变化的技术研究

摘要针对某些通信信道码率时变的特点,探讨标准H．264中三种适应码率变化技术,介绍适应码率变化的方法。     

划分交互式箱粒子概率假设密度滤波法

针对现有的多机动目标追踪问题,将交互式多模型(interacting multiple model,IMM)思想与箱粒子概率假设密度滤波器(box probability hypothesis density filter,Box-PHD)相结合,并针对箱粒子在区间密集杂波等复杂环境下箱体偏大,所导致的箱粒子冗余和目标...     

基于分区租借的大规模作业管理系统

PWS(partitioned workload system)是引入分区化技术以及资源租借技术的作业管理系统(JMS)。分区技术加强了机群系统中资源的可管理性,通过资源租借技术提高了系统资源的利用率。优化的通信方式让PWS能够支持上千节点的大规模机群系统。PWS已经在曙光4000A超级计算机以及相关高性能计算领域中得到了应用。该文介绍了PWS的设计与实现。     

基于非均匀划分的分布式影像数据索引方法

本文介绍了现有的对影像数据管理和索引的方法及其存在的不足，提出了一种基于非均匀划分思想对分布式影像数据进行管理和索引的方法，避免了由于边缘补零带来的时间和空间开销。实验结果表明，本文方法能够支持对分布式多图幅的联合查询以及结果的无缝拼接，而且其时间和空间代价远小于现有方法。     

Multi-scale qualitative location: A direction-based model

Qualitative locations describe the locations of spatial objects by relating them to a reference frame with qualitative relations. Existing models concerned with regional partitions are mainly topology-based and do not consider the effects of scale changes on locations. This study develops a direction-based multi-scale qualitative location (DMQL) model to fill this gap. First, a cell partition is defined by extending the borders of the minimum bounding rectangles of the regions in a regional partition. Relating spatial objects to all regions by a set of directions is equal to representing the objects as a set of cells in a cell partition. Second, due to the multiple cell representations of spatial objects and the changes in direction relations across scales, some approaches are presented to derive the direction changes between regions in different frames, between spatial objects and regions, and between spatial objects at different scales. Third, the location and relation consistencies of qualitative locations are evaluated based on the cell representations of spatial objects at multiple scales through a case study. The results indicate that the DMQL model can locate objects more precisely than the topology-based models.     

基于XML分布式异构数据库“主存”中间件实现

为充分利用数据库的资源，研究了在分布式异构数据库中实现数据分布与交换的“主存”中间件实现方法。利用XML跨平台特性和主存/辅存的工作原理，结合基于服务的中间件技术，运用于分布式异构数据库系统中。系统以访问“主存”中间件服务器中最新XML数据为主，访问相应子系统为辅，通过复制分段方式实现数据的一致性。该方法在一定程度上提高了数据处理效率，实现了数据传输同步机制。     

一种新的快速混合聚类算法

在汲取了传统划分、层次聚类方法优点的基础上,结合图搜索技术,提出了一种新的快速混合聚类算法.该算法主要分为三个步骤:首先将整个数据集"压碎",生成固定数量的原子级聚类;然后处理孤立点;最后采用图搜索技术生成聚类.该算法只需一个参数,能识别任意形状、大小的聚类,时间复杂度在最坏情况下为nn~(1/2).实验表明该算法是有效的.     

Various density light field image coding based on distortion minimization interpolation

In recent years, the light field (LF) as a new imaging modality has attracted wide interest. The large data volume of LF images poses great challenge to LF image coding, and the LF images captured by different devices show significant differences in angular domain. In this paper we propose a view prediction framework to handle LF image coding with various sampling density. All LF images are represented as view arrays. We first partition the views into reference view (RV) set and intermediate view (IV) set. The RVs are rearranged into a pseudo sequence and directly compressed by a video encoder. Other views are then predicted by the RVs. To exploit the four dimensional signal structure, we propose the linear approximation prior (LAP) to reveal the correlation among LF views and efficiently remove the LF data redundancy. Based on the LAP, a distortion minimization interpolation (DMI) method is used to predict IVs. To robustly handle the LF images with different sampling density, we propose an Iteratively Updating depth image based rendering (IU-DIBR) method to extend our DMI. Some auxiliary views are generated to cover the target region and then the DMI calculates reconstruction coefficients for the IVs. Different view partition patterns are also explored. Extensive experiments on different types LF images also valid the efficiency of the proposed method.     

基于凹凸局部二值模式的纹理图像分类

针对传统局部二值模式(LBP)及其扩展方法往往会将具有不同视觉特征的局部邻域赋予相同二值模式值的问题,提出了一种新的凹-凸LBP划分方法。首先通过选择最优参数将具有相同二值模式值的邻域划分为凹凸两类,然后分别统计每类特征并组合在一起进行纹理分类。为验证新方法的性能,实验采用3个在纹理分析领域广泛应用的图像库进行分类实验,结果表明,本文方法明显提高了传统LBP方法的分辨能力。