一种数字波形的链表示方法及其在波形识别中的应用

本文叙述了在保持原始数字波形过零点位置信息的条件下,用几个具有不同斜率的直线 段逼近原始波形的算法.根据波形的复杂度和所要求的精度可以方便地调整基元数目.一般 说来用三个基元组成的链保存了原有波形的大部分信息并可用于对波形的句法识别.在某些 地震信号上进行的试验说明了这种链表示的有效性.     

一种便于自动生成识别规则的图象基元抽取方法

本文提出了一种便于自动生成识别规则的图象基元抽取方法。并将其用于手写字符的识别。结果表明,用本方法得到的图象基元链(句子)对图象的位置、大小、局部形变不敏感,降低了语言的信息冗余度。因而易于由样本图象直接生成识别规则.     

Tool Book 3.0动画制作技巧

高质量的图像对多媒体应用效果有显著的提高,如果再让它们动起来,则更具有实感。Asymetrix公司推出的多媒体著作工具ToolBook3.0在动画制作上有比较强的功能,并且简单易学。下面就介绍一下动画制作的几种方法。 一、移动的对象 大多数动画是一个物体从一个位置变迁到另一个位置,在Toolbook中,每个对象都有一个属性称为位置,用坐标(x,y)来表示,刻度以页面单位计算,一个页面单位等于1/1440英寸,移动一个物体也就是该物体的位置属性的更改。 (1)脚本记录器(Script recorder) 这是一种最简单的动画制作方法,用户只要用鼠标或     

全局结构引导的人造物体参数化基元检测

点云是表达三维数据的常见形式,点云数据提取出的几何基元能够帮助人们快速地理解并处理场景信息,也方便后续其他任务的开展.为了更好地利用人造物体中普遍存在的全局结构关系,增强基元检测过程中全局结构的正向引导,提出参数化基元检测网络——RelationNet,包括2个子模块.首先,为了更好地编码三维点与其所在基元的结构关系,通过空间偏移预测模块预测三维点所在基元中心的偏移向量,提升点对其所在基元的位置感知能力,为后续分割任务提供更多的特征依据;其次,人造物体的基元与基元之间常常具有如平行、垂直、轴对齐等结构关系,为了更好地利用这些关系实现对几何基元检测结果的改进,还包含全局结构关系提取模块,利用基元拟合后获得的参数判断各个基元之间的结构关系,并通过设置相应的损失函数对提取到的结果进行引导监督.在大型ABC数据集与基元监督拟合(SPFN), ParseNet等主流算法进行对比的实验结果表明, RelationNet在基元分割和基元分类任务上的MIoU分别达到85.32%和90.10%,与当前先进方法相比有明显的效果提升.     

三维工业物体的多重描述与识别处理

提出了一种三维工业物体的多重描述与识别方法。在描述中采用了整体形状描述，基元属性描述和关系描述相结合的多重描述策略；在识别过程中，首先根据物体的整体描述产生关于物体身份的初步假设，然后提出三种修剪算法，充分利用关系数据结构的多重约束作为知识启发来修剪搜索树，最后根据距离测度函数实现精匹配。实验验证了上述处理的正确性和一般性。     

三维工业物体的多重描述与识别处理

提出了一种三维工业物体的多重描述与识别方法，在描述中采用了整体形状描述，基元属性描述和关系 描述相结合的多重描述策略；在识别过程中#首先根据物体的整体描述产生关于物体身份的初步假设，然后提出三 种修剪算法，充分利用关系数据结构的多重约束作为知识启发来修剪搜索树#最后根据距离测度函数实现精匹配。 实验验证了上述处理的正确性和一般性。     

基于几何相似特征的石窟造像装饰图案生成方法

针对石窟造像装饰图案设计中图案基元的组合方式不够灵活多变、画面布置与调整耗时、图案基元间的交叉重叠问题,提出一种基于几何相似特征的图案生成方法.首先明确图案属性,利用Freeman链码描述图案基元轮廓信息;然后利用最长公共子序列计算图案基元间的几何相似性特征;接着基于计算结果对图案基元进行设计布局,完成子图案的效果生成;最后依据检测和识别出的图案空间分布模式将子图案进行扩充生成.采用响堂山石窟中的装饰图案基元数据进行实验的结果表明,所提方法不仅解决了图案基元组合优化问题,而且能实现复杂图案的快速生成设计,该方法在图案基元的匹配时间为19.2 s,比人工方法的36.1 s更优.     

基于基元分布的误差可调纹理分类算法

提出一种基于纹理基元分布统计的纹理分类算法，选定一组代表像素变化的基元序列，计算每一个基元在纹理图像中的覆盖比例，用得到的纹理基元属性分布作为描述参数；由于相似纹理其属性也是相似的，同类纹理必然有接近的基元分布参数，计算参与实验的纹理样本的基元分布的互方差及互相关，与代表相似程度的阈值比较判断，由获得的共性来锁定同类纹理；为使同类纹理具有可参照的标准，产生针对每一类纹理的标准类分布。对Brodatz的111纹理不同相似程度的分类结果表明，该方法保证了统计结果与视觉判断的一致性，可用于纹理的分类及识别。     

船载柔性阵基元坐标实时获取技术研究

为了解决船载柔性阵被动定位系统中基元位置不确定的问题,提出了实时获取柔性阵基元坐标的技术方案.利用辅助声源发射直接扩频的DPSK(Differential phase shift keying)信号,根据广义互相关法估计DPSK信号到达各基元的时延,进而计算各基元的位置坐标.利用水池试验和湖上试验对该方法进行了实验验证,用实时获取的阵元坐标计算得到的目标距离与GPS测量的结果相一致.理论与实验分析的结果表明,本文的方法能够准确地实时获取柔性阵基元的坐标信息.     

识别手写汉字的基元模糊关系法

手写汉字中笔划、部件及其位置关系均产生较大变化,这种变化是引起手写汉字特征不稳定的主要因素。为了减小上述不利影响,使手写汉字特征的描述趋于稳定,文章给出了一种基于汉字基元之间的模糊关系识别手写汉字的方法,用汉字基元之间的模糊关系来描述汉字的结构,其优点:一是对汉字基元之间相对位置的变化有较强的适应性,二是不需要对一个汉字中的各个基元在二维平面内进行复杂地排序,汉字的结构可以简化为一个基元模糊关系的集合。     

On the inherent weakness of conditional primitives

Some well-known primitive operations, such as compare-and-swap, can be used, together with read and write, to implement any object in a wait-free manner. However, this paper shows that, for a large class of objects, including counters, queues, stacks, and single-writer snapshots, wait-free implementations using only these primitive operations and a large class of other primitive operations cannot be space efficient: the number of base objects required is at least linear in the number of processes that share the implemented object. The same lower bounds are obtained for implementations of starvation-free mutual exclusion using only primitive operations from this class. For wait-free implementations of a closely related class of one-time objects, lower bounds on the tradeoff between time and space are presented.     

3-d space location and orientation parameter estimation of lambertian spheres and cylinders from a single 2-d image by fitting lines and ellipses to thresholded data

An approach to object location and orientation estimation is discussed in which objects in 3-D space are approximated by chunks of spheres, cylinders, and planes. The surface-shape parameters of these chunks of primitive subobjects are estimated in real time from a single 2-D image assuming a Lambertian reflection model. This processing is realized by partitioning an image into small square windows and processing the windows in parallel. It is assumed that a small window views a portion of one of the spherical, cylindrical or planar chunks. The paper applies standard statistical estimators in new ways to the estimation of the 3-D shape parameters for spherical and cylindrical surfaces. Linear regression and scatter matrix eigenvalue analysis techniques are used here. The algorithms are computationally simple yet are robust and can handle noisy highly variable data.     

改进主动形状模型算法在运动物体定位中的研究与应用

为提高彩色图像中目标物体的定位精准度和鲁棒性,改善传统主动形状模型采用的灰度模型单一搜索,提出了一种新的基于RGB色彩空间三通道的局部搜索策略.根据彩色图像的特点,充分利用目标的颜色信息,把一维灰度模型扩展成RGB空间彩色模型.结合该模型,提出一种基于各颜色分量所占比重权值的自适应综合匹配函数,并通过由粗到精的多级搜索,实现了彩色图像中运动物体的定位.实验结果表明,该方法降低了模型陷入局部最优的概率,并且提高了目标物体定位的精度和收敛速度.     

光线自适应的水下管线识别与定位系统

本文论述了在水下环境下如何通过视觉识别管线并给以精确的定位．提出了水下视 觉系统的总体设计方案．在识别目标时,以目标的颜色为特征,并将颜色从RGB空间转换到H SI空间,使图像处理的速度和特征抽取的鲁棒性得到提高．由于水下环境光照变化剧烈,使 用模糊神经网络来动态调整特征颜色阈值．对水下环境中点和线的精确定位进行了详细的分 析,给出定位算法．最后的实验结果证明了算法的有效性．     

On optimally combining pieces of information, with application to estimating 3-d complex-object position from range data

New asymptotic methods are introduced that permit computationally simple Bayesian recognition and parameter estimation for many large data sets described by a combination of algebraic, geometric, and probabilistic models. The techniques introduced permit controlled decomposition of a large problem into small problems for separate parallel processing where maximum likelihood estimation or Bayesian estimation or recognition can be realized locally. These results can be combined to arrive at globally optimum estimation or recognition. The approach is applied to the maximum likelihood estimation of 3-D complex-object position. To this end, the surface of an object is modeled as a collection of patches of primitive quadrics, i.e., planar, cylindrical, and spherical patches, possibly augmented by boundary segments. The primitive surface-patch models are specified by geometric parameters, reflecting location, orientation, and dimension information. The object-position estimation is based on sets of range data points, each set associated with an object primitive. Probability density functions are introduced that model the generation of range measurement points. This entails the formulation of a noise mechanism in three-space accounting for inaccuracies in the 3-D measurements and possibly for inaccuracies in the 3-D modeling. We develop the necessary techniques for optimal local parameter estimation and primitive boundary or surface type recognition for each small patch of data, and then optimal combining of these inaccurate locally derived parameter estimates in order to arrive at roughly globally optimum object-position estimation.     

Robust and efficient surface reconstruction from contours

We propose a new approach for surface recovery from planar sectional contours. The surface is reconstructed based on the so-called “equal importance criterion,” which suggests that every point in the region contributes equally to the reconstruction process. The problem is then formulated in terms of a partial differential equation, and the solution is efficiently calculated from distance transformation. To make the algorithm valid for different application purposes, both the isosurface and the primitive representations of the object surface are derived. The isosurface is constructed by means of a partial differential equation, which can be solved iteratively. The traditional distance interpolating method, which was used by several researchers for surface reconstruction, is an approximate solution of the equation. The primitive representations are approximated by Voronoi diagram transformation of the surface space. Isosurfaces have the advantage that subsequent geometric analysis of the object can be easily carried out while primitive representation is easy to visualize. The proposed technique allows for surface recovery at any desired resolution, thus avoiding the inherent problems of correspondence, tiling, and branching.     

基于复杂特征融合的改进mean shift目标跟踪

提出一种融合Gabor小波纹理特征与颜色特征的改进mean shift目标跟踪算法.首先,提取移动目标的颜色特征和纹理特征直方图;其次,基于mean shift算法定义融合相似度系数,对特征空间进行融合并得出目标中心位置;再次,通过定义特征自适应系数来融合基于颜色和纹理特征的目标位置;最后,对上述结果进行处理,得到目标最终位置.实验结果表明,该算法在跟踪目标存在变形、噪声、遮挡时能够得到比较理想的跟踪效果.     

对象空间踪迹的自动跟踪与管理

提出了一种在多个观察点对目标空间踪迹自动跟踪的方法(MOTT)。每条踪迹由若干个空间等距的节点连接构成，而节点信息从2个相似摄像头捕捉的视频流中提取。该文构造了一个三维方位模型(3DOM)来确定目标当前的位置，并预测了运动轨迹，构造了一个空间踪迹模型(STM)，用来记录对象行为信息，识别对象行为特征，并通过代理对象分类管理这些踪迹。该方法可在视频防盗、航空视频监控等领域广泛应用。     

Solid Texturing of Soft Objects

Since the shape of a soft object changes in response to its surroundings, it is difficult to give a single position in space as the location of the object. Indeed objects can and do break dynamically into subobjects. This means that you cannot map a solid texture onto such an object simply by using a function of the space coordinates. We have taken a different approach. Our soft objects are modeled as the volume enclosed by an isosurf ace of a field calculated from a set of key points. For each key point, we describe an abstract texture space. Any point on the surface of an object has, associated with each key point, a position in this space and a field contribution. A vector sum of these positions, weighted by the field contributions, is used to select a surface specification from the texture space. Textures mapped with this process retain their consistency during distortion and metamorphoses of objects, permitting a great variety of animation effects.     

Shapes recognition using the straight line Hough transform: theoryand generalization

A shape matching technique based on the straight line Hough transform (SLHT) is presented. In the &thetas;-ρ space, the transform can be expressed as the sum of the translation term and the intrinsic term. This formulation allows the translation, rotation, and intrinsic parameters of the curve to be easily decoupled. A shape signature, called the scalable translation invariant rotation-to-shifting (STIRS) signature, is obtained from the &thetas;-ρ space by computing the distances between pairs of points having the same &thetas; value. This signature is invariant to translation and can be easily normalized, and rotation in the image space corresponds to circular shifting of the signature. Matching two signatures only amounts to computing a 1D correlation. The height and location of a peak (if it exists) indicate the similarity and orientation of the test object with respect to the reference object. The location of the test object is obtained, once the orientation is known, by an inverse transform (voting) from the &thetas;-ρ space to the x-y plane