人脸边缘自适应搜索算法及仿真研究

人脸轮廓线提取是人脸识别中极为重要的内容,一种可靠、精确的人脸边缘提取算法对于身份鉴定技术等方面具有重要的应用价值。该文基于传统的边缘提取算法提出了一种自适应搜索轮廓线算法,首先基于人脸检测结果确定内外轮廓及搜索路径,然后对于每一条搜索路径提取出真正的轮廓点,最后利用人脸轮廓的平滑性通过曲线拟合完成轮廓线提取。该文以彩色人脸图像库数据为例,快速、准确地得到人脸轮廓线。仿真试验结果表明,该算法能在保持边缘检测精度的情况下,克服了噪声对轮廓特征提取的影响,并且对于姿势变化有一定的鲁棒性,具有一定的应用价值。     

融合肤色信息和椭圆环模板的人脸检测

融合肤色信息和人脸轮廓信息,提出了一种新颖的基于肤色信息和人脸轮廓的人脸检测算法.首先利用改进的肤色提取算法对肤色进行分割,分析肤色区域,找出备选人脸;然后对备选人脸区域进行边缘检测,根据边缘检测点进行人脸轮廓特征的匹配,找出入脸的准确位置,并利用马赛克模板排除虚假人脸.实验结果表明,该算法具有较高的准确率,检测速度快...     

防抖动和渗色的视频人脸非边缘分割算法

针对基于2D的视频人脸替换的特定应用中,替换后的人脸出现抖动、渗色等问题,提出一种防抖动与渗色的视频人脸非边缘分割算法。对源人脸和目标人脸进行主动形状模型(ASM)特征点定位,并采用普氏对齐算法将源人脸向目标人脸对齐,再在人脸非边缘区域进行线性插值,得到非最优的人脸非边缘分割轮廓;设计了兼顾前后帧非边缘分割轮廓时间连续性和当前帧非边缘分割轮廓纹理平滑性的能量函数,并采用动态规划算法使得能量最小化,得到最优的人脸非边缘分割轮廓;依次得到后续帧最优的人脸非边缘分割轮廓。实验结果表明,提出的算法有效地防止替换后的人脸出现抖动和渗色的现象,具有一定的应用价值。     

自适应搜索目标的快速彩色复合人脸检测方法

针对AdaBoost人脸检测方法搜索时间较长,不利于在手机等嵌入式平台上应用的现状,提出了一种结合肤色分割、人脸几何特征和AdaBoost的自适应搜索窗口和搜索步长的快速人脸检测方法。该算法在HSV颜色空间对图像进行分割,结合人脸几何特征对分割后的灰度图像进行面积滤波。最后提取滤波后的图像轮廓,结合经验系数得到自适应搜索窗口和搜索步长。实验结果表明,自适应算法不仅能检测出不同尺寸的人脸,而且检测速度快,能节省51.17%的搜索时间。     

基于混合能量活动轮廓模型的人脸分割方法

由于受到面部五官、饰物等因素的影响,传统几何活动轮廓模型获取人脸外轮廓会产生凹陷、分片等现象.针对人脸图像的特点,将边缘外张力能量及肤色能量与全局能量结合,提出一种基于混合能量泛函的几何活动轮廓模型,有效地避免了这些问题.首先,根据演化曲线的邻域信息赋予边缘点向外的张力,使曲线能够克服面部特征及面部饰物的干扰,引导其向外轮廓方向演化.鉴于肤色是面部最重要的特征,提出肤色能量,进一步提高了模型的鲁棒性.此外,提出一种基于单高斯模型的改进算法,能够估计出接近实际人脸外轮廓的初始位置,为轮廓演化奠定了基础.在两个公共人脸库上进行测试,该方法能够得到准确的人脸分割效果;以手工分割的结果为基准,该算法定位精度明显优于传统的全局能量模型和局部能量模型.还用日常照片创建一个包含不同姿态、光照、复杂背景等因素、复杂的人脸库,分割结果表明,该方法能够克服这些因素的影响,取得了准确而稳定的人脸分割结果.     

一种鲁棒的人脸特征定位方法

提出了一种基于AdaBoost算法和C-V方法的人脸特征定位方法。首先根据AdaBoost算法训练样本得到脸、眼、鼻、嘴4个检测器;然后结合人脸边缘图像的先验规则,使用人脸检测器提取人脸区域;接着利用眼、鼻、嘴检测器从人脸区域中检测出人脸特征所在的矩形区域;最后利用C-V方法从各个特征区域中分割出人脸特征的轮廓,进而得到人脸关键特征点的位置。在DTU IMM人脸测试集上,眼睛的检测率为100%,鼻子的检测率为95.3%,嘴巴的检测率为98.4%,提取出的特征点位置准确。实验结果表明方法是有效和鲁棒的。     

综合利用人脸特征和活动轮廓技术的人脸检测及跟踪算法

把基于静态图像分割的人脸检测技术同活动轮廓技术相结合，提出了一种在视频序列中检测和跟踪人脸的算法．它在Y、U、V联合梯度的基础土实施分水岭运算，并利用人脸的宽高比、颜色、结构等特征进行人脸逐级判别，从而确定人脸住置，然后用基于骨架的活动轮廓进行精确定位和帧间跟踪，从而较好地实现了视频序列中的人脸检测与跟踪问题。算法具有较强的鲁棒性，对于运动比较平缓、脸部轮廓比较清晰的情况，可以进行长时间跟踪。本算法在面向内容的可伸缩视频压缩编码系统中得到应用。     

基于语义分割的简洁线条肖像画生成方法

针对目前主流的线条提取算法对于区域对比度不明显的边缘的检测能力较弱,且对于所有区域采用无差别、统一化的处理策略,所生成的线条画往往较复杂,非常不利于机器人机械臂绘图的问题,本文提出了一种基于语义分割的简洁线条肖像画生成方法(concise line portrait generation based on semantic segmentation, CLPG-SS)。首先,对人脸图像进行语义分割,将人脸划分为不同的区域,基于不同区域提取边缘轮廓与五官细节线条,进行边缘切向流优化,从而加强方向信息;在此基础上,利用线条图来生成调和图像,并利用优化后的边缘切向流、人脸语义分割结果以及调和图像,针对不同的分割区域调整线条提取方法的参数,实现对细节无关区域的线条过滤和细节重点区域的线条加强,生成简洁线条肖像画。实验结果表明:本文提出的CLPG-SS方法能够有效提取人脸主轮廓线条,并针对不同区域实现了对细节线条的针对性调节,提高了机器人机械臂的绘制效率。     

基于Adaboost和最小割算法的视频人脸检测

Adaboost算法是一种被广泛应用于人脸检测的分类器学习方法,通过Haar-like特征和样本的学习和训练,形成一个强分类器,能有效地区分人脸跟非人脸.文中提出一种Adaboost结合最小割算法的人脸提取方法,该方法着眼于图像中的轮廓及肤色信息,对每个点设置一个权值,寻找一条权值最小的边界,准确提取出人脸.实验结果表明,Adaboost和最小割的人脸提取算法,分割效果较好,且耗时较小.     

基于轮廓信息的人脸检测

针对彩色图像提出了一种基于肤色模型、脸部轮廓信息以及眼睛特征的人脸检测算法.采用基于YCbCr色彩空间的肤色分割模型,初步筛选人脸的候选区域;在此基础上进行边缘检测,获得人脸轮廓信息,并利用遗传算法拟合脸部的椭圆;在椭圆的水平方向根据眼睛的几何特征来检测"眼睛对",再根据"三停五眼"来定位人脸,并利用左右对称性验证人脸.实验表明,该算法对于彩色图像的正面人脸检测具有良好的效果.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.